Java DB Reference Manual
Version 10.3
Derby Document build:
July 24, 2007, 1:24:20 PM (EDT)
Version 10.3 Java DB Reference Manual
Contents
Copyright •
License •
Relationship between Java DB and Derby •
About this guide •
Purpose of this document •
Audience •
How this guide is organized •
SQL language reference •
Capitalization and special characters •
SQL identifiers •
Rules for SQL92 identifiers •
SQL92Identifier •
column-Name •
correlation-Name •
new-table-Name •
schemaName •
Simple-column-Name •
synonym-Name •
table-Name •
view-Name •
index-Name •
constraint-Name •
cursor-Name •
TriggerName •
AuthorizationIdentifier •
Statements •
Interaction with the dependency system •
ALTER TABLE statement •
CALL (PROCEDURE) statement •
CREATE statements •
DECLARE GLOBAL TEMPORARY TABLE statement •
DELETE statement •
DROP statements •
GRANT statement •
INSERT statement •
LOCK TABLE statement •
RENAME statements •
REVOKE statement •
SET statements •
SELECT statement •
UPDATE statement •
SQL clauses •
CONSTRAINT clause •
FOR UPDATE clause •
FROM clause •
GROUP BY clause •
HAVING clause •
ORDER BY clause •
WHERE clause •
WHERE CURRENT OF clause •
SQL expressions •
SelectExpression •
TableExpression •
VALUES expression •
Expression precedence •
Boolean expressions •
Dynamic parameters •
JOIN operations •
INNER JOIN operation •
LEFT OUTER JOIN operation •
RIGHT OUTER JOIN operation •
SQL queries •
Query •
ScalarSubquery •
TableSubquery •
Built-in functions •
Standard built-in functions •
Aggregates (set functions) •
ABS or ABSVAL function •
ACOS function •
ASIN function •
ATAN function •
AVG function •
BIGINT function •
CASE expressions •
CAST function •
CEIL or CEILING function •
CHAR function •
Concatenation operator •
COS function •
COUNT function •
COUNT(*) function •
CURRENT DATE function •
CURRENT_DATE function •
CURRENT ISOLATION function •
CURRENT SCHEMA function •
CURRENT TIME function •
CURRENT_TIME function •
CURRENT TIMESTAMP function •
CURRENT_TIMESTAMP function •
CURRENT_USER function •
DATE function •
DAY function •
DEGREES function •
DOUBLE function •
EXP function •
FLOOR function •
HOUR function •
IDENTITY_VAL_LOCAL function •
INTEGER function •
LCASE or LOWER function •
LENGTH function •
LN or LOG function •
LOG10 function •
LOCATE function •
LTRIM function •
MAX function •
MIN function •
MINUTE function •
MOD function •
MONTH function •
NULLIF expressions •
PI function •
RADIANS function •
RTRIM function •
SECOND function •
SESSION_USER function •
SIN function •
SMALLINT function •
SQRT function •
SUBSTR function •
SUM function •
TAN function •
TIME function •
TIMESTAMP function •
TRIM function •
UCASE or UPPER function •
USER function •
VARCHAR function •
XMLEXISTS operator •
XMLPARSE operator •
XMLQUERY operator •
XMLSERIALIZE operator •
YEAR function •
Built-in system functions •
SYSCS_UTIL.SYSCS_CHECK_TABLE system function •
SYSCS_UTIL.SYSCS_GET_DATABASE_PROPERTY system function •
SYSCS_UTIL.SYSCS_GET_RUNTIMESTATISTICS system function •
Built-in system procedures •
SYSCS_UTIL.SYSCS_BACKUP_DATABASE system procedure •
SYSCS_UTIL.SYSCS_BACKUP_DATABASE_NOWAIT system procedure •
SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE system procedure •
SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE_NOWAIT system procedure •
SYSCS_UTIL.SYSCS_CHECKPOINT_DATABASE system procedure •
SYSCS_UTIL.SYSCS_COMPRESS_TABLE system procedure •
SYSCS_UTIL.SYSCS_INPLACE_COMPRESS_TABLE system procedure •
SYSCS_UTIL.SYSCS_DISABLE_LOG_ARCHIVE_MODE system procedure •
SYSCS_UTIL.SYSCS_EXPORT_TABLE system procedure •
SYSCS_UTIL.SYSCS_EXPORT_TABLE_LOBS_TO_EXTFILE system procedure •
SYSCS_UTIL.SYSCS_EXPORT_QUERY system procedure •
SYSCS_UTIL.SYSCS_EXPORT_QUERY_LOBS_TO_EXTFILE system procedure •
SYSCS_UTIL.SYSCS_IMPORT_DATA system procedure •
SYSCS_UTIL.SYSCS_IMPORT_DATA_LOBS_FROM_EXTFILE system procedure •
SYSCS_UTIL.SYSCS_IMPORT_TABLE system procedure •
SYSCS_UTIL.SYSCS_IMPORT_TABLE_LOBS_FROM_EXTFILE system procedure •
SYSCS_UTIL.SYSCS_FREEZE_DATABASE system procedure •
SYSCS_UTIL.SYSCS_UNFREEZE_DATABASE system procedure •
SYSCS_UTIL.SYSCS_RELOAD_SECURITY_POLICY system procedure •
SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY system procedure •
SYSCS_UTIL.SYSCS_SET_RUNTIMESTATISTICS system procedure •
SYSCS_UTIL.SYSCS_SET_STATISTICS_TIMING system procedure •
SYSCS_DIAG diagnostic tables and functions •
Data types •
Built-In type overview •
Numeric types •
Data type assignments and comparison, sorting, and ordering •
BIGINT data type •
BLOB data type •
CHAR data type •
CHAR FOR BIT DATA data type •
CLOB data type •
DATE data type •
DECIMAL data type •
DOUBLE data type •
DOUBLE PRECISION data type •
FLOAT data type •
INTEGER data type •
LONG VARCHAR data type •
LONG VARCHAR FOR BIT DATA data type •
NUMERIC data type •
REAL data type •
SMALLINT data type •
TIME data type •
TIMESTAMP data type •
VARCHAR data type •
VARCHAR FOR BIT DATA data type •
XML data type •
SQL reserved words •
Derby support for SQL-92 features •
Derby system tables •
SYSALIASES system table •
SYSCHECKS system table •
SYSCOLPERMS system table •
SYSCOLUMNS system table •
SYSCONGLOMERATES system table •
SYSCONSTRAINTS system table •
SYSDEPENDS system table •
SYSFILES system table •
SYSFOREIGNKEYS system table •
SYSKEYS system table •
SYSROUTINEPERMS system table •
SYSSCHEMAS system table •
SYSSTATISTICS system table •
SYSSTATEMENTS system table •
SYSTABLEPERMS system table •
SYSTABLES system table •
SYSTRIGGERS system table •
SYSVIEWS system table •
Derby exception messages and SQL states •
SQL error messages and exceptions •
JDBC reference •
Core JDBC java.sql classes, interfaces, and methods •
java.sql.Driver interface •
java.sql.Driver.getPropertyInfo method •
java.sql.DriverManager.getConnection method •
Derby database connection URL syntax •
Syntax of database connection URLs for applications with embedded databases •
Additional SQL syntax •
Attributes of the Derby database connection URL •
java.sql.Connection interface •
java.sql.Connection.setTransactionIsolation method •
java.sql.Connection.setReadOnly method •
java.sql.Connection.isReadOnly method •
Connection functionality not supported •
java.sql.DatabaseMetaData interface •
DatabaseMetaData result sets •
java.sql.DatabaseMetaData.getProcedureColumns method •
Parameters to getProcedureColumns •
Columns in the ResultSet returned by getProcedureColumns •
java.sql.DatabaseMetaData.getBestRowIdentifier method •
java.sql.Statement interface •
ResultSet objects •
java.sql.CallableStatement interface •
CallableStatements and OUT Parameters •
CallableStatements and INOUT Parameters •
java.sql.SQLException class •
java.sql.PreparedStatement interface •
Prepared statements and streaming columns •
java.sql.ResultSet interface •
ResultSets and streaming columns •
java.sql.ResultSetMetaData interface •
java.sql.SQLWarning class •
java.sql.SQLXML interface •
Mapping of java.sql.Types to SQL types •
Mapping of java.sql.Blob and java.sql.Clob interfaces •
JDBC 2.0 features •
java.sql.CallableStatement interface: supported JDBC 2.0 methods •
java.sql.Connection interface: supported JDBC 2.0 methods •
java.sql.DatabaseMetaData interface: supported JDBC 2.0 methods •
java.sql.PreparedStatement interface: supported JDBC 2.0 methods •
java.sql.ResultSet interface: supported JDBC 2.0 methods •
java.sql.ResultSetMetaData interface: supported JDBC 2.0 methods •
java.sql.Statement interface: supported JDBC 2.0 methods •
java.sql.BatchUpdateException class •
JDBC Package for Connected Device Configuration/Foundation Profile (JSR169) •
JDBC 3.0 features •
java.sql.Connection interface: supported JDBC 3.0 methods •
java.sql.DatabaseMetaData interface: supported JDBC 3.0 methods •
java.sql.ParameterMetaData interface: supported JDBC 3.0 methods •
java.sql.PreparedStatement interface: supported JDBC 3.0 methods •
java.sql.Savepoint interface •
java.sql.Statement interface: supported JDBC 3.0 methods •
JDBC 4.0-only features •
Refined subclasses of SQLException •
java.sql.Connection interface: JDBC 4.0 features •
java.sql.DatabaseMetaData interface: JDBC 4.0 features •
java.sql.Statement interface: JDBC 4.0 features •
javax.sql.DataSource interface: JDBC 4.0 features •
JDBC escape syntax •
JDBC escape keyword for call statements •
JDBC escape syntax •
JDBC escape syntax for LIKE clauses •
JDBC escape syntax for fn keyword •
JDBC escape syntax for outer joins •
JDBC escape syntax for time formats •
JDBC escape syntax for date formats •
JDBC escape syntax for timestamp formats •
Setting attributes for the database connection URL •
bootPassword=key attribute •
collation=collation attribute •
create=true attribute •
createFrom=path attribute •
databaseName=nameofDatabase attribute •
dataEncryption=true attribute •
encryptionKey=key attribute •
encryptionProvider=providerName attribute •
encryptionAlgorithm=algorithm attribute •
logDevice=logDirectoryPath attribute •
newEncryptionKey=key attribute •
newBootPassword=newPassword attribute •
password=userPassword attribute •
restoreFrom=path attribute •
rollForwardRecoveryFrom=path attribute •
securityMechanism=value attribute •
shutdown=true attribute •
territory=ll_CC attribute •
user=userName attribute •
ssl=sslMode attribute •
Creating a connection without specifying attributes •
J2EE Compliance: Java Transaction API and javax.sql Interfaces •
The JTA API •
Notes on Product Behavior •
javax.sql: JDBC Interfaces •
Derby API •
Stand-alone tools and utilities •
JDBC implementation classes •
JDBC driver •
Data Source Classes •
Miscellaneous utilities and interfaces •
Supported territories •
Derby limitations •
Limitations for database manager values •
DATE, TIME, and TIMESTAMP limitations •
Limitations on identifier length •
Numeric limitations •
String limitations •
XML limitations •
Trademarks •
•
Java DB Reference Manual
Apache Software FoundationJava DB Reference ManualApache Derby
Copyright
Copyright 2004-2007 The Apache Software Foundation
Copyright 2007 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, California 95054, U.S.A.
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0.
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Relationship between Java(TM) DB and Derby
Java(TM) DB is a relational database management system that is based on the Java programming language and SQL. Java DB is a commercial release of the Apache Software Foundation's (ASF) open source relational database project. The Apache project is called Derby.
The Java DB product includes Derby without any modification whatsoever to the underlying source code.
Technical support is available for purchase for the Java DB product through Sun.
Because Java DB and Derby have the same functionality, the Java DB documentation refers to the core functionality as Derby.
Java DB Version 10.3 is based on the Derby Version 10.3 release. References to "Derby" in the Java DB documentation refer to the Version 10.3 release of Apache Derby.
About this guide
For general information about the Derby documentation, such as a complete list of books, conventions, and further reading, see Getting Started with Java DB.
Purpose of this document
This book, the Java DB Reference Manual, provides reference information about Derby. It covers Derby's SQL language, the Derby implementation of JDBC, Derby system catalogs, Derby error messages, Derby properties, and SQL keywords.
Audience
This book is a reference for Derby users, typically application developers. Derby users who are not familiar with the SQL standard or the Java programming language will benefit from consulting books on those topics.
Derby users who want a how-to approach to working with Derby or an introduction to Derby concepts should read the Java DB Developer's Guide.
How this guide is organized
This guide includes the following sections:

• |  | SQL language reference Reference information about Derby's SQL language, including manual pages for statements, functions, and other syntax elements.
• |  | SQL reserved words SQL keywords beyond the standard SQL-92 keywords.
• |  | Derby support for SQL-92 features A list of SQL-92 features that Derby does and does not support.
• |  | Derby system tables Reference information about the Derby system catalogs.
• |  | Derby exception messages and SQL states Information about Derby exception messages.
• |  | JDBC reference Information about Derby's implementation of the JDBC interface including support for JDBC 2.0 features.
• |  | Setting attributes for the database connection URL Information about the supported attributes to Derby's JDBC database connection URL.
• |  | J2EE Compliance: Java Transaction API and javax.sql Interfaces Information about the supported attributes to Derby's support for the Java Transaction API.
• |  | Derby API Notes about proprietary APIs for Derby.

SQL language reference
Derby implements an SQL-92 core subset, as well as some SQL-99 features.
This section provides an overview of the current SQL language by describing the statements, built-in functions, data types, expressions, and special characters it contains.
Capitalization and special characters
Using the classes and methods of JDBC, you submit SQL statements to Derby as strings. The character set permitted for strings containing SQL statements is Unicode. Within these strings, the following rules apply:

• |  | Double quotation marks delimit special identifiers referred to in SQL-92 as delimited identifiers.
• |  | Single quotation marks delimit character strings.
• |  | Within a character string, to represent a single quotation mark or apostrophe, use two single quotation marks. (In other words, a single quotation mark is the escape character for a single quotation mark.) A double quotation mark does not need an escape character. To represent a double quotation mark, simply use a double quotation mark. However, note that in a Java program, a double quotation mark requires the backslash escape character. Example:
    -- a single quotation mark is the escape character
    -- for a single quotation mark

    VALUES 'Joe''s umbrella'
    -- in ij, you don't need to escape the double quotation marks
    VALUES 'He said, "hello!"'

    n = stmt.executeUpdate(
        "UPDATE aTable setStringcol = 'He said, \"hello!\"'");
• |  | SQL keywords are case-insensitive. For example, you can type the keyword SELECT as SELECT, Select, select, or sELECT.
• |  | SQL-92-style identifiers are case-insensitive (see SQL92Identifier), unless they are delimited.
• |  | Java-style identifiers are always case-sensitive.
• |  | * is a wildcard within a SelectExpression. See The * wildcard. It can also be the multiplication operator. In all other cases, it is a syntactical metasymbol that flags items you can repeat 0 or more times.
• |  | % and _ are character wildcards when used within character strings following a LIKE operator (except when escaped with an escape character). See Boolean expressions.
• |  | Two dashes (--) and a newline character delimit a comment, as per the SQL-92 standard. The two dashes start the comment and the newline character ends the comment.

SQL identifiers
An identifier is the representation within the language of items created by the user, as opposed to language keywords or commands. Some identifiers stand for dictionary objects, which are the objects you create- such as tables, views, indexes, columns, and constraints- that are stored in a database. They are called dictionary objects because Derby stores information about them in the system tables, sometimes known as a data dictionary. SQL also defines ways to alias these objects within certain statements.
Each kind of identifier must conform to a different set of rules. Identifiers representing dictionary objects must conform to SQL-92 identifier rules and are thus called SQL92Identifiers.
Rules for SQL92 identifiers
Ordinary identifiers are identifiers not surrounded by double quotation marks. Delimited identifiers are identifiers surrounded by double quotation marks.
An ordinary identifier must begin with a letter and contain only letters, underscore characters (_), and digits. The permitted letters and digits include all Unicode letters and digits, but Derby does not attempt to ensure that the characters in identifiers are valid in the database's locale.
A delimited identifier can contain any characters within the double quotation marks. The enclosing double quotation marks are not part of the identifier; they serve only to mark its beginning and end. Spaces at the end of a delimited identifier are insignificant (truncated). Derby translates two consecutive double quotation marks within a delimited identifier as one double quotation mark-that is, the "translated" double quotation mark becomes a character in the delimited identifier.
Periods within delimited identifiers are not separators but are part of the identifier (the name of the dictionary object being represented).
So, in the following example:

    "A.B"

is a dictionary object, while

    "A"."B"

is a dictionary object qualified by another dictionary object (such as a column named "B" within the table "A").
SQL92Identifier
An SQL92Identifier is a dictionary object identifier that conforms to the rules of SQL-92. SQL-92 states that identifiers for dictionary objects are limited to 128 characters and are case-insensitive (unless delimited by double quotes), because they are automatically translated into uppercase by the system. You cannot use reserved words as identifiers for dictionary objects unless they are delimited. If you attempt to use a name longer than 128 characters, SQLException X0X11 is raised.
Derby defines keywords beyond those specified by the SQL-92 standard (see SQL reserved words).
Example

    -- the view name is stored in the
    -- system catalogs as ANIDENTIFIER
    CREATE VIEW AnIdentifier (RECEIVED) AS VALUES 1
    -- the view name is stored in the system
    -- catalogs with case intact
    CREATE VIEW "ACaseSensitiveIdentifier" (RECEIVED) AS VALUES 1

This section describes the rules for using SQL92Identifiers to represent the following dictionary objects.
Qualifying dictionary objects
Since some dictionary objects can be contained within other objects, you can qualify those dictionary object names. Each component is separated from the next by a period. An SQL92Identifier is "dot-separated." You qualify a dictionary object name in order to avoid ambiguity.
column-Name
In many places in the SQL syntax, you can represent the name of a column by qualifying it with a table-Name or correlation-Name.
In some situations, you cannot qualify a column-Name with a table-Name or a correlation-Name, but must use a Simple-column-Name instead. Those situations are:

• |  | creating a table (CREATE TABLE statement)
• |  | specifying updatable columns in a cursor
• |  | in a column's correlation name in a SELECT expression (see SelectExpression)
• |  | in a column's correlation name in a TableExpression (see TableExpression)

You cannot use correlation-Names for updatable columns; using correlation-Names in this way will cause an SQL exception. For example:

    SELECT c11 AS col1, c12 AS col2, c13 FROM t1 FOR UPDATE of c11,c13

In this example, the correlation-Name col1 FOR c11 is not permitted because c11 is listed in the FOR UPDATE list of columns. You can use the correlation-Name FOR c12 because it is not in the FOR UPDATE list.
Syntax

    [ { table-Name | correlation-Name } . ] SQL92Identifier

Example

    -- C.Country is a column-Name qualified with a
    -- correlation-Name.
    SELECT C.Country
    FROM APP.Countries C

correlation-Name
A correlation-Name is given to a table expression in a FROM clause as a new name or alias for that table. You do not qualify a correlation-Name with a schema-Name.
You cannot use correlation-Names for updatable columns; using correlation-Names in this way will cause an SQL exception. For example:

    SELECT c11 AS col1, c12 AS col2, c13 FROM t1 FOR UPDATE of c11,c13

In this example, the correlation-Name col1 FOR c11 is not permitted because c11 is listed in the FOR UPDATE list of columns. You can use the correlation-Name FOR c12 because it is not in the FOR UPDATE list.
Syntax

    SQL92Identifier

Example

    -- C is a correlation-Name
    SELECT C.NAME
    FROM SAMP.STAFF C

new-table-Name
A new-table-Name represents a renamed table. You cannot qualify a new-table-Name with a schema-Name.
Syntax

    SQL92Identifier

Example

    -- FlightBooks is a new-table-Name that does not include a schema-Name
    RENAME TABLE FLIGHTAVAILABILITY TO FLIGHTAVAILABLE

schemaName
A schemaName represents a schema. Schemas contain other dictionary objects, such as tables and indexes. Schemas provide a way to name a subset of tables and other dictionary objects within a database.
You can explicitly create or drop a schema. The default user schema is the APP schema (if no user name is specified at connection time). You cannot create objects in schemas starting with SYS.
Thus, you can qualify references to tables with the schema name. When a schemaName is not specified, the default schema name is implicitly inserted. System tables are placed in the SYS schema. You must qualify all references to system tables with the SYS schema identifier. For more information about system tables, see Derby system tables.
A schema is hierarchically the highest level of dictionary object, so you cannot qualify a schemaName.
Syntax

    SQL92Identifier

Example

    -- SAMP.EMPLOYEE is a table-Name qualified by a schemaName
    SELECT COUNT(*) FROM SAMP.EMPLOYEE
    -- You must qualify system catalog names with their schema, SYS
    SELECT COUNT(*) FROM SYS.SysColumns

Simple-column-Name
A Simple-column-Name is used to represent a column when it cannot be qualified by a table-Name or correlation-Name. This is the case when the qualification is fixed, as it is in a column definition within a CREATE TABLE statement.
Syntax

    SQL92Identifier

Example

    -- country is a Simple-column-Name
    CREATE TABLE CONTINENT (COUNTRY VARCHAR(26) NOT NULL PRIMARY KEY,
    COUNTRY_ISO_CODE CHAR(2), REGION VARCHAR(26))

synonym-Name
A synonym-Name represents a synonym for a table or a view. You can qualify a synonym-Name with a schema-Name.
Syntax

    [ schemaName. ] SQL92Identifier

table-Name
A table-Name represents a table. You can qualify a table-Name with a schemaName.
Syntax

    [ schemaName. ] SQL92Identifier

Example

    -- SAMP.PROJECT is a table-Name that includes a schemaName
    SELECT COUNT(*) FROM SAMP.PROJECT

view-Name
A view-Name represents a table or a view. You can qualify a view-Name with a schema-Name.
Syntax

    [ schemaName. ] SQL92Identifier

Example

    -- This is a View qualified by a schema-Name
    SELECT COUNT(*) FROM SAMP.EMP_RESUME

index-Name
An index-Name represents an index. Indexes live in schemas, so you can qualify their names with schema-Names. Indexes on system tables are in the SYS schema.
Syntax

    [ schemaName . ] SQL92Identifier

Example

    DROP INDEX APP.ORIGINDEX;
    -- OrigIndex is an index-Name without a schema-Name
    CREATE INDEX ORIGINDEX ON FLIGHTS (ORIG_AIRPORT)

constraint-Name
You cannot qualify constraint-names.
Syntax

    SQL92Identifier

Example

    -- country_fk2 is a constraint name
    CREATE TABLE DETAILED_MAPS (COUNTRY_ISO_CODE CHAR(2)
    CONSTRAINT country_fk2 REFERENCES COUNTRIES)

cursor-Name
A cursor-Name refers to a cursor. No SQL language command exists to assign a name to a cursor. Instead, you use the JDBC API to assign names to cursors or to retrieve system-generated names. For more information, see the Java DB Developer's Guide. If you assign a name to a cursor, you can refer to that name from within SQL statements.
You cannot qualify a cursor-Name.
Syntax

    SQL92Identifier

Example

    stmt.executeUpdate("UPDATE SAMP.STAFF SET COMM = " +
    "COMM + 20 " + "WHERE CURRENT OF " + ResultSet.getCursorName());

TriggerName
A TriggerName refers to a trigger created by a user.
Syntax

    [ schemaName . ] SQL92Identifier

Example

    DROP TRIGGER TRIG1

AuthorizationIdentifier
User names within the Derby system are known as authorization identifiers. The authorization identifier represents the name of the user, if one has been provided in the connection request. The default schema for a user is equal to its authorization identifier. User names can be case-sensitive within the authentication system, but they are always case-insensitive within Derby's authorization system unless they are delimited. For more information, see the Java DB Developer's Guide.
Syntax

    SQL92Identifier

Example

    CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY(
        'derby.database.fullAccessUsers', 'Amber,FRED')

Statements
This section provides manual pages for both high-level language constructs and parts thereof. For example, the CREATE INDEX statement is a high-level statement that you can execute directly via the JDBC interface. This section also includes clauses, which are not high-level statements and which you cannot execute directly but only as part of a high-level statement. The ORDER BY and WHERE clauses are examples of this kind of clause. Finally, this section also includes some syntactically complex portions of statements called expressions, for example SelectExpression and TableSubquery. These clauses and expressions receive their own manual pages for ease of reference.
Unless it is explicitly stated otherwise, you can execute or prepare and then execute all the high-level statements, which are all marked with the word statement, via the interfaces provided by JDBC. This manual indicates whether an expression can be executed as a high-level statement.
The sections provide general information about statement use, and descriptions of the specific statements.
Interaction with the dependency system
Derby internally tracks the dependencies of prepared statements, which are SQL statements that are precompiled before being executed. Typically they are prepared (precompiled) once and executed multiple times.
Prepared statements depend on the dictionary objects and statements they reference. (Dictionary objects include tables, columns, constraints, indexes, views, and triggers.) Removing or modifying the dictionary objects or statements on which they depend invalidates them internally, which means that Derby will automatically try to recompile the statement when you execute it. If the statement fails to recompile, the execution request fails. However, if you take some action to restore the broken dependency (such as restoring the missing table), you can execute the same prepared statement, because Derby will recompile it automatically at the next execute request.
Statements depend on one another-an UPDATE WHERE CURRENT statement depends on the statement it references. Removing the statement on which it depends invalidates the UPDATE WHERE CURRENT statement.
In addition, prepared statements prevent execution of certain DDL statements if there are open results sets on them.
Manual pages for each statement detail what actions would invalidate that statement, if prepared.
Here is an example using the Derby tool ij:

    ij> CREATE TABLE mytable (mycol INT);
    0 rows inserted/updated/deleted
    ij> INSERT INTO mytable VALUES (1), (2), (3);
    3 rows inserted/updated/deleted
    -- this example uses the ij command prepare,
    -- which prepares a statement
    ij> prepare p1 AS 'INSERT INTO MyTable VALUES (4)';
    -- p1 depends on mytable;
    ij> execute p1;
    1 row inserted/updated/deleted
    -- Derby  executes it without recompiling
    ij> CREATE INDEX i1 ON mytable(mycol);
    0 rows inserted/updated/deleted
    -- p1 is temporarily invalidated because of new index
    ij> execute p1;
    1 row inserted/updated/deleted
    -- Derby  automatically recompiles p1 and executes it
    ij> DROP TABLE mytable;
    0 rows inserted/updated/deleted
    -- Derby  permits you to drop table
    -- because result set of p1 is closed
    -- however, the statement p1 is temporarily invalidated
    ij> CREATE TABLE mytable (mycol INT);
    0 rows inserted/updated/deleted
    ij> INSERT INTO mytable VALUES (1), (2), (3);
    3 rows inserted/updated/deleted
    ij> execute p1;
    1 row inserted/updated/deleted
    -- Because p1 is invalid, Derby  tries to recompile it
    -- before executing.
    -- It is successful and executes.
    ij> DROP TABLE mytable;
    0 rows inserted/updated/deleted
    -- statement p1 is now invalid,
    -- and this time the attempt to recompile it
    -- upon execution will fail
    ij> execute p1;
    ERROR 42X05: Table/View 'MYTABLE' does not exist.

ALTER TABLE statement
The ALTER TABLE statement allows you to:

• |  | add a column to a table
• |  | add a constraint to a table
• |  | drop an existing constraint from a table
• |  | increase the width of a VARCHAR, CHAR VARYING, and CHARACTER VARYING column
• |  | override row-level locking for the table (or drop the override)
• |  | change the increment value and start value of the identity column
• |  | change the nullability constraint for a column
• |  | change the default value for a column

Syntax

    ALTER TABLE table-Name
    {
        ADD COLUMN column-definition |
        ADD CONSTRAINT clause |
        DROP { PRIMARY KEY | FOREIGN KEY constraint-name | UNIQUE
    	 constraint-name | CHECK constraint-name | CONSTRAINT constraint-name }
        ALTER [ COLUMN ] column-alteration |
        LOCKSIZE { ROW | TABLE }
    }

column-definition

    Simple-column-NameDataType
    [ Column-level-constraint ]*
    [ [ WITH ] DEFAULT {ConstantExpression | NULL } ]

column-alteration

    column-Name SET DATA TYPE VARCHAR(integer) |
    column-name SET INCREMENT BY integer-constant |
    column-name RESTART WITH integer-constant |
    column-name [ NOT ] NULL |
    column-name [ WITH ] DEFAULT default-value

In the column-alteration, SET INCREMENT BY integer-constant, specifies the interval between consecutive values of the identity column. The next value to be generated for the identity column will be determined from the last assigned value with the increment applied. The column must already be defined with the IDENTITY attribute.
RESTART WITH integer-constant specifies the next value to be generated for the identity column. RESTART WITH is useful for a table that has an identity column that was defined as GENERATED BY DEFAULT and that has a unique key defined on that identity column. Because GENERATED BY DEFAULT allows both manual inserts and system generated values, it is possible that manually inserted values can conflict with system generated values. To work around such conflicts, use the RESTART WITH syntax to specify the next value that will be generated for the identity column. Consider the following example, which involves a combination of automatically generated data and manually inserted data:

    CREATE TABLE tauto(i INT GENERATED BY DEFAULT AS IDENTITY, k INT)
    CREATE UNIQUE INDEX tautoInd ON tauto(i)
    INSERT INTO tauto(k) values 1,2

The system will automatically generate values for the identity column. But now you need to manually insert some data into the identity column:

    INSERT INTO tauto VALUES (3,3)
    INSERT INTO tauto VALUES (4,4)
    INSERT INTO tauto VALUES (5,5)

The identity column has used values 1 through 5 at this point. If you now want the system to generate a value, the system will generate a 3, which will result in a unique key exception because the value 3 has already been manually inserted. To compensate for the manual inserts, issue an ALTER TABLE statement for the identity column with RESTART WITH 6:

    ALTER TABLE tauto ALTER COLUMN i RESTART WITH 6

ALTER TABLE does not affect any view that references the table being altered. This includes views that have an "*" in their SELECT list. You must drop and re-create those views if you wish them to return the new columns.
Adding columns
The syntax for the column-definition for a new column is the same as for a column in a CREATE TABLE statement. This means that a column constraint can be placed on the new column within the ALTER TABLE ADD COLUMN statement. However, a column with a NOT NULL constraint can be added to an existing table if you give a default value; otherwise, an exception is thrown when the ALTER TABLE statement is executed.
Just as in CREATE TABLE, if the column definition includes a unique or primary key constraint, the column cannot contain null values, so the NOT NULL attribute must also be specified (SQLSTATE 42831).
Note: If a table has an UPDATE trigger without an explicit column list, adding a column to that table in effect adds that column to the implicit update column list upon which the trigger is defined, and all references to transition variables are invalidated so that they pick up the new column.
Adding constraints
ALTER TABLE ADD CONSTRAINT adds a table-level constraint to an existing table. Any supported table-level constraint type can be added via ALTER TABLE. The following limitations exist on adding a constraint to an existing table:

• |  | When adding a foreign key or check constraint to an existing table, Derby checks the table to make sure existing rows satisfy the constraint. If any row is invalid, Derby throws a statement exception and the constraint is not added.
• |  | All columns included in a primary key must contain non null data and be unique. ALTER TABLE ADD UNIQUE or PRIMARY KEY provide a shorthand method of defining a primary key composed of a single column. If PRIMARY KEY is specified in the definition of column C, the effect is the same as if the PRIMARY KEY(C) clause were specified as a separate clause. The column cannot contain null values, so the NOT NULL attribute must also be specified.

For information on the syntax of constraints, see CONSTRAINT clause. Use the syntax for table-level constraint when adding a constraint with the ADD TABLE ADD CONSTRAINT syntax.
Dropping constraints
ALTER TABLE DROP CONSTRAINT drops a constraint on an existing table. To drop an unnamed constraint, you must specify the generated constraint name stored in SYS.SYSCONSTRAINTS as a delimited identifier.
Dropping a primary key, unique, or foreign key constraint drops the physical index that enforces the constraint (also known as a backing index).
Modifying columns
The column-alteration allows you to alter the named column in the following ways:

• |  | Increasing the length of an existing VARCHAR column. CHARACTER VARYING or CHAR VARYING can be used as synonyms for the VARCHAR keyword. To increase the width of a column of these types, specify the data type and new size after the column name. You are not allowed to decrease the width or to change the data type. You are not allowed to increase the width of a column that is part of a primary or unique key referenced by a foreign key constraint or that is part of a foreign key constraint.
• |  | Specifying the interval between consecutive values of the identity column. To set an interval between consecutive values of the identity column, specify the integer-constant. You must previously define the column with the IDENTITY attribute (SQLSTATE 42837). If there are existing rows in the table, the values in the column for which the SET INCREMENT default was added do not change.
• |  | Modifying the nullability constraint of a column. You can add the NOT NULL constraint to an existing column. To do so there must not be existing NULL values for the column in the table. You can remove the NOT NULL constraint from an existing column. To do so the column must not be used in a PRIMARY KEY or UNIQUE constraint.
• |  | Changing the default value for a column.

Setting defaults
You can specify a default value for a new column. A default value is the value that is inserted into a column if no other value is specified. If not explicitly specified, the default value of a column is NULL. If you add a default to a new column, existing rows in the table gain the default value in the new column.
For more information about defaults, see CREATE TABLE statement.
Changing the lock granularity for the table
The LOCKSIZE clause allows you to override row-level locking for the specific table, if your system uses the default setting of row-level locking. (If your system is set for table-level locking, you cannot change the locking granularity to row-level locking, although Derby allows you to use the LOCKSIZE clause in such a situation without throwing an exception.) To override row-level locking for the specific table, set locking for the table to TABLE. If you created the table with table-level locking granularity, you can change locking back to ROW with the LOCKSIZE clause in the ALTER TABLE STATEMENT. For information about why this is sometimes useful, see Tuning Java DB.
Examples

    -- Add a new column with a column-level constraint
    -- to an existing table
    -- An exception will be thrown if the table
    -- contains any rows
    -- since the newcol will be initialized to NULL
    -- in all existing rows in the table
    ALTER TABLE CITIES ADD COLUMN REGION VARCHAR(26)
    CONSTRAINT NEW_CONSTRAINT CHECK (REGION IS NOT NULL);

    -- Add a new unique constraint to an existing table
    -- An exception will be thrown if duplicate keys are found
    ALTER TABLE SAMP.DEPARTMENT
    ADD CONSTRAINT NEW_UNIQUE UNIQUE (DEPTNO);

    -- add a new foreign key constraint to the
    -- Cities table. Each row in Cities is checked
    -- to make sure it satisfied the constraints.
    -- if any rows don't satisfy the constraint, the
    -- constraint is not added
    ALTER TABLE CITIES ADD CONSTRAINT COUNTRY_FK
    Foreign Key (COUNTRY) REFERENCES COUNTRIES (COUNTRY);

    -- Add a primary key constraint to a table
    -- First, create a new table
    CREATE TABLE ACTIVITIES (CITY_ID INT NOT NULL,
    SEASON CHAR(2), ACTIVITY VARCHAR(32) NOT NULL);
    -- You will not be able to add this constraint if the
    -- columns you are including in the primary key have
    -- null data or duplicate values.
    ALTER TABLE Activities ADD PRIMARY KEY (city_id, activity);

    -- Drop a primary key constraint from the CITIES table

    ALTER TABLE Cities DROP CONSTRAINT Cities_PK;
    -- Drop a foreign key constraint from the CITIES table
    ALTER TABLE Cities DROP CONSTRAINT COUNTRIES_FK;
    -- add a DEPTNO column with a default value of 1
    ALTER TABLE SAMP.EMP_ACT ADD COLUMN DEPTNO INT DEFAULT 1;
    -- increase the width of a VARCHAR column
    ALTER TABLE SAMP.EMP_PHOTO ALTER PHOTO_FORMAT SET DATA TYPE VARCHAR(30);
    -- change the lock granularity of a table
    ALTER TABLE SAMP.SALES LOCKSIZE TABLE;

    -- Remove the NOT NULL constraint from the MANAGER column
    ALTER TABLE Employees ALTER COLUMN Manager NULL;
    -- Add the NOT NULL constraint to the SSN column
    ALTER TABLE Employees ALTER COLUMN ssn NOT NULL;

    -- Change the default value for the SALARY column
    ALTER TABLE Employees ALTER COLUMN Salary DEFAULT 1000.0

Results
An ALTER TABLE statement causes all statements that are dependent on the table being altered to be recompiled before their next execution. ALTER TABLE is not allowed if there are any open cursors that reference the table being altered.
CALL (PROCEDURE) statement
The CALL (PROCEDURE) statement is used to call procedures. A call to a procedure does not return any value.
Syntax

    CALL procedure-Name ( [ expression [, expression]* ] )

Example

    CREATE PROCEDURE SALES.TOTAL_REVENUE(IN S_MONTH INTEGER,
        IN S_YEAR INTEGER, OUT TOTAL DECIMAL(10,2))
        PARAMETER STYLE JAVA READS SQL DATA LANGUAGE JAVA EXTERNAL NAME
        'com.acme.sales.calculateRevenueByMonth';
    CALL SALES.TOTAL_REVENUE(?,?,?);

CREATE statements
Use the Create statements with functions, indexes, procedures, schemas, synonyms, tables, triggers, and views.
CREATE FUNCTION statement
The CREATE FUNCTION statement allows you to create Java functions, which you can then use in an expression.
The function owner and the database owner automatically gain the EXECUTE privilege on the function, and are able to grant this privilege to other users. The EXECUTE privileges cannot be revoked from the function and database owners.
Syntax

    CREATE FUNCTION function-name ( [ FunctionParameter
       [, FunctionParameter] ] * ) RETURNS DataType [ FunctionElement ] *

function-Name

    [ schemaName. ] SQL92Identifier

If schema-Name is not provided, the current schema is the default schema. If a qualified procedure name is specified, the schema name cannot begin with SYS.
FunctionParameter

    [ parameter-Name ] DataType

PararameterName must be unique within a function.
The syntax of DataType is described in Data types.
Note: Data-types such as BLOB, CLOB, LONG VARCHAR, LONG VARCHAR FOR BIT DATA, and XML are not allowed as parameters in a CREATE FUNCTION statement.
FunctionElement

     {
    | LANGUAGE { JAVA }
    | EXTERNAL NAME string
    | PARAMETER STYLE JAVA
    | { NO SQL | CONTAINS SQL | READS SQL DATA }
    | { RETURNS NULL ON NULL INPUT | CALLED ON NULL INPUT }
     }

LANGUAGE
JAVA- the database manager will call the function as a public static method in a Java class.
EXTERNAL NAME string
String describes the Java method to be called when the function is executed, and takes the following form:

    class_name.method_name

The External Name cannot have any extraneous spaces.
PARAMETER STYLE
JAVA - The function will use a parameter-passing convention that conforms to the Java language and SQL Routines specification. INOUT and OUT parameters will be passed as single entry arrays to facilitate returning values. Result sets are returned through additional parameters to the Java method of type java.sql.ResultSet[] that are passed single entry arrays.
Derby does not support long column types (for example Long Varchar, BLOB, and so on). An error will occur if you try to use one of these long column types.
NO SQL, CONTAINS SQL, READS SQL DATA
Indicates whether the function issues any SQL statements and, if so, what type.
CONTAINS SQL
Indicates that SQL statements that neither read nor modify SQL data can be executed by the function. Statements that are not supported in any function return a different error.
NO SQL
Indicates that the function cannot execute any SQL statements
READS SQL DATA
Indicates that some SQL statements that do not modify SQL data can be included in the function. Statements that are not supported in any stored function return a different error. This is the default value.
RETURNS NULL ON NULL INPUT or CALLED ON NULL INPUT
Specifies whether the function is called if any of the input arguments is null. The result is the null value.
RETURNS NULL ON NULL INPUT
Specifies that the function is not invoked if any of the input arguments is null. The result is the null value.
CALLED ON NULL INPUT
Specifies that the function is invoked if any or all input arguments are null. This specification means that the function must be coded to test for null argument values. The function can return a null or non-null value. This is the default setting.
The function elements may appear in any order, but each type of element can only appear once. A function definition must contain these elements:

• |  | LANGUAGE
• |  | PARAMETER STYLE
• |  | EXTERNAL NAME

Example

    CREATE FUNCTION TO_DEGREES(RADIANS DOUBLE) RETURNS DOUBLE
    PARAMETER STYLE JAVA NO SQL LANGUAGE JAVA
    EXTERNAL NAME 'java.lang.Math.toDegrees'

CREATE INDEX statement
A CREATE INDEX statement creates an index on a table. Indexes can be on one or more columns in the table.
Syntax

    CREATE [UNIQUE] INDEX index-Name
    ON table-Name ( Simple-column-Name [ ASC | DESC ]
        [ , Simple-column-Name [ ASC | DESC ]] * )

The maximum number of columns for an index key in Derby is 16.
An index name cannot exceed 128 characters.
A column must not be named more than once in a single CREATE INDEX statement. Different indexes can name the same column, however.
Derby can use indexes to improve the performance of data manipulation statements (see Tuning Java DB). In addition, UNIQUE indexes provide a form of data integrity checking.
Index names are unique within a schema. (Some database systems allow different tables in a single schema to have indexes of the same name, but Derby does not.) Both index and table are assumed to be in the same schema if a schema name is specified for one of the names, but not the other. If schema names are specified for both index and table, an exception will be thrown if the schema names are not the same. If no schema name is specified for either table or index, the current schema is used.
By default, Derby uses the ascending order of each column to create the index. Specifying ASC after the column name does not alter the default behavior. The DESC keyword after the column name causes Derby to use descending order for the column to create the index. Using the descending order for a column can help improve the performance of queries that require the results in mixed sort order or descending order and for queries that select the minimum or maximum value of an indexed column.
If a qualified index name is specified, the schema name cannot begin with SYS.
Indexes and constraints
Unique, primary key, and foreign key constraints generate indexes that enforce or "back" the constraint (and are thus sometimes called backing indexes). If a column or set of columns has a UNIQUE or PRIMARY KEY constraint on it, you can not create an index on those columns. Derby has already created it for you with a system-generated name. System-generated names for indexes that back up constraints are easy to find by querying the system tables if you name your constraint. Adding a PRIMARY KEY or UNIQUE constraint when an existing UNIQUE index exists on the same set of columns will result in two physical indexes on the table for the same set of columns. One index is the original UNIQUE index and one is the backing index for the new constraint.
To find out the name of the index that backs a constraint called FLIGHTS_PK:

    SELECT CONGLOMERATENAME FROM SYS.SYSCONGLOMERATES,
    SYS.SYSCONSTRAINTS WHERE
    SYS.SYSCONGLOMERATES.TABLEID = SYSCONSTRAINTS.TABLEID
    AND CONSTRAINTNAME = 'FLIGHTS_PK'

    CREATE INDEX OrigIndex ON Flights(orig_airport);
    -- money is usually ordered from greatest to least,
    -- so create the index using the descending order
    CREATE INDEX PAY_DESC ON SAMP.EMPLOYEE (SALARY);
    -- use a larger page size for the index
    call SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.storage.pageSize','8192');
    CREATE INDEX IXSALE ON SAMP.SALES (SALES);
    call SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.storage.pageSize',NULL);

Page size and key size
Note: The size of the key columns in an index must be equal to or smaller than half the page size. If the length of the key columns in an existing row in a table is larger than half the page size of the index, creating an index on those key columns for the table will fail. This error only occurs when creating an index if an existing row in the table fails the criteria. After an index is created, inserts may fail if the size of their associated key exceeds the criteria.
Statement dependency system
Prepared statements that involve SELECT, INSERT, UPDATE, UPDATE WHERE CURRENT, DELETE, and DELETE WHERE CURRENT on the table referenced by the CREATE INDEX statement are invalidated when the index is created. Open cursors on the table are not affected.
CREATE PROCEDURE statement
The CREATE PROCEDURE statement allows you to create Java stored procedures, which you can then call using the CALL PROCEDURE statement.
The procedure owner and the database owner automatically gain the EXECUTE privilege on the procedure, and are able to grant this privilege to other users. The EXECUTE privileges cannot be revoked from the procedure and database owners.
Syntax

    CREATE PROCEDURE procedure-Name ( [ ProcedureParameter
       [, ProcedureParameter] ] * )
    [ ProcedureElement ] *

procedure-Name

    [ schemaName. ] SQL92Identifier

If schema-Name is not provided, the current schema is the default schema. If a qualified procedure name is specified, the schema name cannot begin with SYS.
ProcedureParameter

    [ { IN | OUT | INOUT } ] [ parameter-Name ] DataType

The default value for a parameter is IN. ParameterName must be unique within a procedure.
The syntax of DataType is described in Data types.
Note: Data-types such as BLOB, CLOB, LONG VARCHAR, LONG VARCHAR FOR BIT DATA, and XML are not allowed as parameters in a CREATE PROCEDURE statement.
ProcedureElement

     {
    | [ DYNAMIC ] RESULT SETS INTEGER
    | LANGUAGE { JAVA }
    | EXTERNAL NAME string
    | PARAMETER STYLE JAVA
    | { NO SQL | MODIFIES SQL DATA | CONTAINS SQL | READS SQL DATA }
     }

DYNAMIC RESULT SETS integer
Indicates the estimated upper bound of returned result sets for the procedure. Default is no (zero) dynamic result sets.
LANGUAGE
JAVA- the database manager will call the procedure as a public static method in a Java class.
EXTERNAL NAME string
String describes the Java method to be called when the procedure is executed, and takes the following form:

    class_name.method_name

The External Name cannot have any extraneous spaces.
PARAMETER STYLE
JAVA - The procedure will use a parameter-passing convention that conforms to the Java language and SQL Routines specification. INOUT and OUT parameters will be passed as single entry arrays to facilitate returning values. Result sets are returned through additional parameters to the Java method of type java.sql.ResultSet [] that are passed single entry arrays.
Derby does not support long column types (for example Long Varchar, BLOB, and so on). An error will occur if you try to use one of these long column types.
NO SQL, CONTAINS SQL, READS SQL DATA, MODIFIES SQL DATA
Indicates whether the stored procedure issues any SQL statements and, if so, what type.
CONTAINS SQL
Indicates that SQL statements that neither read nor modify SQL data can be executed by the stored procedure. Statements that are not supported in any stored procedure return a different error. MODIFIES SQL DATA is the default value.
NO SQL
Indicates that the stored procedure cannot execute any SQL statements
READS SQL DATA
Indicates that some SQL statements that do not modify SQL data can be included in the stored procedure. Statements that are not supported in any stored procedure return a different error.
MODIFIES SQL DATA
Indicates that the stored procedure can execute any SQL statement except statements that are not supported in stored procedures.
The procedure elements may appear in any order, but each type of element can only appear once. A procedure definition must contain these elements:

• |  | LANGUAGE
• |  | PARAMETER STYLE
• |  | EXTERNAL NAME

Example

    CREATE PROCEDURE SALES.TOTAL_REVENUE(IN S_MONTH INTEGER,
    IN S_YEAR INTEGER, OUT TOTAL DECIMAL(10,2))
    PARAMETER STYLE JAVA READS SQL DATA LANGUAGE JAVA EXTERNAL NAME
    'com.acme.sales.calculateRevenueByMonth'

CREATE SCHEMA statement
A schema is a way to logically group objects in a single collection and provide a unique namespace for objects.
Syntax

    CREATE SCHEMA { [ schemaName AUTHORIZATION user-name ] | [ schemaName ] |
    [ AUTHORIZATION user-name ] }

The CREATE SCHEMA statement is used to create a schema. A schema name cannot exceed 128 characters. Schema names must be unique within the database.
CREATE SCHEMA examples
To create a schema for airline-related tables and give the authorization ID anita access to all of the objects that use the schema, use the following syntax:

    CREATE SCHEMA FLIGHTS AUTHORIZATION anita

To create a schema employee-related tables, use the following syntax:

    CREATE SCHEMA EMP

To create a schema that uses the same name as the authorization ID takumi, use the following syntax:

    CREATE SCHEMA AUTHORIZATION takumi

To create a table called availability in the EMP and FLIGHTS schemas, use the following syntax:

    CREATE TABLE FLIGHTS.AVAILABILITY
    	(FLIGHT_ID CHAR(6) NOT NULL, SEGMENT_NUMBER INT NOT NULL,
    	FLIGHT_DATE DATE NOT NULL, ECONOMY_SEATS_TAKEN INT,
    	BUSINESS_SEATS_TAKEN INT, FIRSTCLASS_SEATS_TAKEN INT,
    	CONSTRAINT FLT_AVAIL_PK
    	PRIMARY KEY (FLIGHT_ID, SEGMENT_NUMBER, FLIGHT_DATE))

    CREATE TABLE EMP.AVAILABILITY
    	(HOTEL_ID INT NOT NULL, BOOKING_DATE DATE NOT NULL, ROOMS_TAKEN INT,
    	CONSTRAINT HOTELAVAIL_PK PRIMARY KEY (HOTEL_ID, BOOKING_DATE))

CREATE SYNONYM statement
Use the CREATE SYNONYM statement to provide an alternate name for a table or a view that is present in the same schema or another schema. You can also create synonyms for other synonyms, resulting in nested synonyms. A synonym can be used instead of the original qualified table or view name in SELECT, INSERT, UPDATE, DELETE or LOCK TABLE statements. You can create a synonym for a table or a view that doesn't exist, but the target table or view must be present before the synonym can be used.
Synonyms share the same namespace as tables or views. You cannot create a synonym with the same name as a table that already exists in the same schema. Similarly, you cannot create a table or view with a name that matches a synonym already present.
A synonym can be defined for a table/view that does not exist when you create the synonym. If the table or view doesn't exist, you will receive a warning message (SQLSTATE 01522). The referenced object must be present when you use a synonym in a DML statement.
You can create a nested synonym (a synonym for another synonym), but any attempt to create a synonym that results in a circular reference will return an error message (SQLSTATE 42916).
Synonyms cannot be defined in system schemas. All schemas starting with 'SYS' are considered system schemas and are reserved by Derby.
A synonym cannot be defined on a temporary table. Attempting to define a synonym on a temporary table will return an error message (SQLSTATE XCL51).
Syntax

    CREATE SYNONYM synonym-Name FOR { view-Name | table-Name }

The synonym-Name in the statement represents the synonym name you are giving the target table or view, while the view-Name or table-Name represents the original name of the target table or view.
Example
CREATE SYNONYM SAMP.T1 FOR SAMP.TABLEWITHLONGNAME
CREATE TABLE statement
A CREATE TABLE statement creates a table. Tables contain columns and constraints, rules to which data must conform. Table-level constraints specify a column or columns. Columns have a data type and can specify column constraints (column-level constraints).
The table owner and the database owner automatically gain the following privileges on the table and are able to grant these privileges to other users:

• |  | INSERT
• |  | SELECT
• |  | REFERENCES
• |  | TRIGGER
• |  | UPDATE

These privileges cannot be revoked from the table and database owners.
For information about constraints, see CONSTRAINT clause.
You can specify a default value for a column. A default value is the value to be inserted into a column if no other value is specified. If not explicitly specified, the default value of a column is NULL. See Column default.
You can specify storage properties such as page size for a table by calling the SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY system procedure.
If a qualified table name is specified, the schema name cannot begin with SYS.
Syntax
There are two different variants of the CREATE TABLE statement, depending on whether you are specifying the column definitions and constraints, or whether you are modeling the columns after the results of a query expression:

    CREATE TABLE table-Name
      {
          ( {column-definition | Table-level constraint}
          [ , {column-definition | Table-level constraint} ] * )
      |
          [ ( column-name [ , column-name ] * ) ]
          AS query-expression
          WITH NO DATA
       }

Example

    CREATE TABLE HOTELAVAILABILITY
         (HOTEL_ID INT NOT NULL, BOOKING_DATE DATE NOT NULL,
    	ROOMS_TAKEN INT DEFAULT 0, PRIMARY KEY (HOTEL_ID, BOOKING_DATE));
    -- the table-level primary key definition allows you to
    -- include two columns in the primary key definition
    PRIMARY KEY (hotel_id, booking_date))
    -- assign an identity column attribute to an INTEGER
    -- column, and also define a primary key constraint
    -- on the column
    CREATE TABLE PEOPLE
    	(PERSON_ID INT NOT NULL GENERATED ALWAYS AS IDENTITY
    	CONSTRAINT PEOPLE_PK PRIMARY KEY, PERSON VARCHAR(26));
    -- assign an identity column attribute to a SMALLINT
    -- column with an initial value of 5 and an increment value
    -- of 5.
    CREATE TABLE GROUPS
    	(GROUP_ID SMALLINT NOT NULL GENERATED ALWAYS AS IDENTITY
    	(START WITH 5, INCREMENT BY 5), ADDRESS VARCHAR(100), PHONE VARCHAR(15));

Note: For more examples of CREATE TABLE statements using the various constraints, see CONSTRAINT clause.
CREATE TABLE ... AS ...
With the alternate form of the CREATE TABLE statement, the column names and/or the column data types can be specified by providing a query. The columns in the query result are used as a model for creating the columns in the new table.
If no column names are specified for the new table, then all the columns in the result of the query expression are used to create same-named columns in the new table, of the corresponding data type(s). If one or more column names are specified for the new table, then the same number of columns must be present in the result of the query expression; the data types of those columns are used for the corresponding columns of the new table.
The WITH NO DATA clause specifies that the data rows which result from evaluating the query expression are not used; only the names and data types of the columns in the query result are used. The WITH NO DATA clause must be specified; in a future release, Derby may be modified to allow the WITH DATA clause to be provided, which would indicate that the results of the query expression should be inserted into the newly-created table. In the current release, however, only the WITH NO DATA form of the statement is accepted.
Example

    -- create a new table using all the columns and data types
    -- from an existing table:
    CREATE TABLE T3 AS SELECT * FROM T1 WITH NO DATA;
    -- create a new table, providing new names for the columns, but
    -- using the data types from the columns of an existing table:
    CREATE TABLE T3 (A,B,C,D,E) AS SELECT * FROM T1 WITH NO DATA;
    -- create a new table, providing new names for the columns,
    -- using the data types from the indicated columns of an existing table:
    CREATE TABLE T3 (A,B,C) AS SELECT V,DP,I FROM T1 WITH NO DATA;
    -- This example shows that the columns in the result of the
    -- query expression may be unnamed expressions, but their data
    -- types can still be used to provide the data types for the
    -- corresponding named columns in the newly-created table:
    CREATE TABLE T3 (X,Y) AS SELECT 2*I,2.0*F FROM T1 WITH NO DATA;

column-definition:

    Simple-column-NameDataType
        [ Column-level-constraint ]*
        [ [ WITH ] DEFAULT { ConstantExpression | NULL }
           |generated-column-spec ]
        [ Column-level-constraint ]*

The syntax of Data-Type is described in Data types.
The syntaxes of Column-level-constraint and Table-level constraint are described in CONSTRAINT clause.
Column default
For the definition of a default value, a ConstantExpression is an expression that does not refer to any table. It can include constants, date-time special registers, current schemas, users, and null.
generated-column-spec:

    [ GENERATED { ALWAYS | BY DEFAULT } AS IDENTITY
    [ ( START WITH IntegerConstant
    [ ,INCREMENT BY IntegerConstant] ) ]  ]  ]

Identity column attributes
For SMALLINT, INT, and BIGINT columns with identity attributes, Derby automatically assigns increasing integer values to the column. Identity column attributes behave like other defaults in that when an insert statement does not specify a value for the column, Derby automatically provides the value. However, the value is not a constant; Derby automatically increments the default value at insertion time.
The IDENTITY keyword can only be specified if the data type associated with the column is one of the following exact integer types.

• |  | SMALLINT
• |  | INT
• |  | BIGINT

There are two kinds of identity columns in Derby: those which are GENERATED ALWAYS and those which are GENERATED BY DEFAULT.
GENERATED ALWAYS
An identity column that is GENERATED ALWAYS will increment the default value on every insertion and will store the incremented value into the column. Unlike other defaults, you cannot insert a value directly into or update an identity column that is GENERATED ALWAYS. Instead, either specify the DEFAULT keyword when inserting into the identity column, or leave the identity column out of the insertion column list altogether. For example:

    create table greetings
    	(i int generated always as identity, ch char(50));
    insert into greetings values (DEFAULT, 'hello');
    insert into greetings(ch) values ('bonjour');

Automatically generated values in a GENERATED ALWAYS identity column are unique. Creating an identity column does not create an index on the column.
GENERATED BY DEFAULT
An identity column that is GENERATED BY DEFAULT will only increment and use the default value on insertions when no explicit value is given. Unlike GENERATED ALWAYS columns, you can specify a particular value in an insertion statement to be used instead of the generated default value.
To use the generated default, either specify the DEFAULT keyword when inserting into the identity column, or just leave the identity column out of the insertion column list. To specify a value, included it in the insertion statement. For example:

    create table greetings
    	(i int generated by default as identity, ch char(50));
    -- specify value "1":
    insert into greetings values (1, 'hi');
    -- use generated default
    insert into greetings values (DEFAULT, 'salut');
    -- use generated default
    insert into greetings(ch) values ('bonjour');

Note that unlike a GENERATED ALWAYS column, a GENERATED BY DEFAULT column does not guarantee uniqueness. Thus, in the above example, the hi and salut rows will both have an identity value of "1", because the generated column starts at "1" and the user-specified value was also "1". To prevent duplication, especially when loading or importing data, create the table using the START WITH value which corresponds to the first identity value that the system should assign. To check for this condition and disallow it, you can use a primary key or unique constraint on the GENERATED BY DEFAULT identity column.
By default, the initial value of an identity column is 1, and the amount of the increment is 1. You can specify non-default values for both the initial value and the interval amount when you define the column with the key words STARTS WITH and INCREMENT BY. And if you specify a negative number for the increment value, Derbydecrements the value with each insert. If this value is 0, or positive, Derby increments the value with each insert.
The maximum and minimum values allowed in identity columns are determined by the data type of the column. Attempting to insert a value outside the range of values supported by the data type raises an exception.
Table 1. Maximum and Minimum Values for Columns with Generated Column Specs

Data type | Maximum Value | Minimum Value
SMALLINT | 32767 (java.lang.Short.MAX_VALUE) | -32768 (java.lang.Short.MIN_VALUE)
INT | 2147483647 (java.lang.Integer.MAX_VALUE) | -2147483648 (java.lang.Integer.MIN_VALUE)
BIGINT | 9223372036854775807 (java.lang.Long.MAX_VALUE) | -9223372036854775808 (java.lang.Long.MIN_VALUE)

Automatically generated values in an identity column are unique. Use a primary key or unique constraint on a column to guarantee uniqueness. Creating an identity column does not create an index on the column.
The IDENTITY_VAL_LOCAL function is a non-deterministic function that returns the most recently assigned value for an identity column. See IDENTITY_VAL_LOCAL function for more information.
Note: Specify the schema, table, and column name using the same case as those names are stored in the system tables--that is, all upper case unless you used delimited identifiers when creating those database objects.
Derby keeps track of the last increment value for a column in a cache. It also stores the value of what the next increment value will be for the column on disk in the AUTOINCREMENTVALUE column of the SYS.SYSCOLUMNS system table. Rolling back a transaction does not undo this value, and thus rolled-back transactions can leave "gaps" in the values automatically inserted into an identity column. Derby behaves this way to avoid locking a row in SYS.SYSCOLUMNS for the duration of a transaction and keeping concurrency high.
When an insert happens within a triggered-SQL-statement, the value inserted by the triggered-SQL-statement into the identity column is available from ConnectionInfo only within the trigger code. The trigger code is also able to see the value inserted by the statement that caused the trigger to fire. However, the statement that caused the trigger to fire is not able to see the value inserted by the triggered-SQL-statement into the identity column. Likewise, triggers can be nested (or recursive). An SQL statement can cause trigger T1 to fire. T1 in turn executes an SQL statement that causes trigger T2 to fire. If both T1 and T2 insert rows into a table that cause Derby to insert into an identity column, trigger T1 cannot see the value caused by T2's insert, but T2 can see the value caused by T1's insert. Each nesting level can see increment values generated by itself and previous nesting levels, all the way to the top-level SQL statement that initiated the recursive triggers. You can only have 16 levels of trigger recursion.
Example

    create table greetings
      (i int generated by default as identity (START WITH 2, INCREMENT BY 1),
      ch char(50));
    -- specify value "1":
    insert into greetings values (1, 'hi');
    -- use generated default
    insert into greetings values (DEFAULT, 'salut');
    -- use generated default
    insert into greetings(ch) values ('bonjour');

CREATE TRIGGER statement
A trigger defines a set of actions that are executed when a database event occurs on a specified table. A database event is a delete, insert, or update operation. For example, if you define a trigger for a delete on a particular table, the trigger's action occurs whenever someone deletes a row or rows from the table.
Along with constraints, triggers can help enforce data integrity rules with actions such as cascading deletes or updates. Triggers can also perform a variety of functions such as issuing alerts, updating other tables, sending e-mail, and other useful actions.
You can define any number of triggers for a single table, including multiple triggers on the same table for the same event.
You can create a trigger in any schema where you are the schema owner. To create a trigger on a table that you do not own, you must be granted the TRIGGER privilege on that table. The database owner can also create triggers on any table in any schema.
The trigger does not need to reside in the same schema as the table on which the trigger is defined.
If a qualified trigger name is specified, the schema name cannot begin with SYS.
Syntax

    CREATE TRIGGER TriggerName
    { AFTER | NO CASCADE BEFORE }
    { INSERT | DELETE | UPDATE [ OF column-Name [, column-Name]* ] }
    ON table-Name
    [ ReferencingClause ]
    [ FOR EACH { ROW | STATEMENT } ] [ MODE DB2SQL ]
    Triggered-SQL-statement

Before or after: when triggers fire
Triggers are defined as either Before or After triggers.

• |  | Before triggers fire before the statement's changes are applied and before any constraints have been applied. Before triggers can be either row or statement triggers (see Statement versus row triggers).
• |  | After triggers fire after all constraints have been satisfied and after the changes have been applied to the target table. After triggers can be either row or statement triggers (see Statement versus row triggers).

Insert, delete, or update: what causes the trigger to fire
A trigger is fired by one of the following database events, depending on how you define it (see Syntax above):

• |  | INSERT
• |  | UPDATE
• |  | DELETE

You can define any number of triggers for a given event on a given table. For update, you can specify columns.
Referencing old and new values: the referencing clause
Many triggered-SQL-statements need to refer to data that is currently being changed by the database event that caused them to fire. The triggered-SQL-statement might need to refer to the new (post-change or "after") values.
Derby provides you with a number of ways to refer to data that is currently being changed by the database event that caused the trigger to fire. Changed data can be referred to in the triggered-SQL-statement using transition variables or transition tables. The referencing clause allows you to provide a correlation name or alias for these transition variables by specifying OLD/NEW AS correlation-Name .
For example, if you add the following clause to the trigger definition:

    REFERENCING OLD AS DELETEDROW

you can then refer to this correlation name in the triggered-SQL-statement:

    DELETE FROM HotelAvailability WHERE hotel_id = DELETEDROW.hotel_id

The OLD and NEW transition variables map to a java.sql.ResultSet with a single row.
Note: Only row triggers (see Statement versus row triggers) can use the transition variables. INSERT row triggers cannot reference an OLD row. DELETE row triggers cannot reference a NEW row.
For statement triggers, transition tables serve as a table identifier for the triggered-SQL-statement or the trigger qualification. The referencing clause allows you to provide a correlation name or alias for these transition tables by specifying OLD_TABLE/NEW_TABLE AS correlation-Name
For example:

    REFERENCING OLD_TABLE AS DeletedHotels

allows you to use that new identifier (DeletedHotels) in the triggered-SQL-statement:

    DELETE FROM HotelAvailability WHERE hotel_id IN
        (SELECT hotel_id FROM DeletedHotels)

The old and new transition tables map to a java.sql.ResultSet with cardinality equivalent to the number of rows affected by the triggering event.
Note: Only statement triggers (see Statement versus row triggers) can use the transition tables. INSERT statement triggers cannot reference an OLD table. DELETE statement triggers cannot reference a NEW table.
The referencing clause can designate only one new correlation or identifier and only one old correlation or identifier. Row triggers cannot designate an identifier for a transition table and statement triggers cannot designate a correlation for transition variables.
Statement versus row triggers
You have the option to specify whether a trigger is a statement trigger or a row trigger. If it is not specified in the CREATE TRIGGER statement via FOR EACH clause, then the trigger is a statement trigger by default.

• |  | statement triggers A statement trigger fires once per triggering event and regardless of whether any rows are modified by the insert, update, or delete event.
• |  | row triggers A row trigger fires once for each row affected by the triggering event. If no rows are affected, the trigger does not fire.

Note: An update that sets a column value to the value that it originally contained (for example, UPDATE T SET C = C) causes a row trigger to fire, even though the value of the column is the same as it was prior to the triggering event.
Triggered-SQL-statement
The action defined by the trigger is called the triggered-SQL-statement (in Syntax above, see the last line). It has the following limitations:

• |  | It must not contain any dynamic parameters (?).
• |  | It must not create, alter, or drop the table upon which the trigger is defined.
• |  | It must not add an index to or remove an index from the table on which the trigger is defined.
• |  | It must not add a trigger to or drop a trigger from the table upon which the trigger is defined.
• |  | It must not commit or roll back the current transaction or change the isolation level.
• |  | Before triggers cannot have INSERT, UPDATE or DELETE statements as their action.
• |  | Before triggers cannot call procedures that modify SQL data as their action.

The triggered-SQL-statement can reference database objects other than the table upon which the trigger is declared. If any of these database objects is dropped, the trigger is invalidated. If the trigger cannot be successfully recompiled upon the next execution, the invocation throws an exception and the statement that caused it to fire will be rolled back.
For more information on triggered-SQL-statements, see the Java DB Developer's Guide.
Order of execution
When a database event occurs that fires a trigger, Derby performs actions in this order:

• |  | It fires No Cascade Before triggers.
• |  | It performs constraint checking (primary key, unique key, foreign key, check).
• |  | It performs the insert, update, or delete.
• |  | It fires After triggers.

When multiple triggers are defined for the same database event for the same table for the same trigger time (before or after), triggers are fired in the order in which they were created.

    -- Statements and triggers:

    CREATE TRIGGER t1 NO CASCADE BEFORE UPDATE ON x
      FOR EACH ROW MODE DB2SQL
      values app.notifyEmail('Jerry', 'Table x is about to be updated');

    CREATE TRIGGER FLIGHTSDELETE
      AFTER DELETE ON FLIGHTS
      REFERENCING OLD_TABLE AS DELETEDFLIGHTS
      FOR EACH STATEMENT
      DELETE FROM FLIGHTAVAILABILITY WHERE FLIGHT_ID IN
      (SELECT FLIGHT_ID FROM DELETEDFLIGHTS);

    CREATE TRIGGER FLIGHTSDELETE3
      AFTER DELETE ON FLIGHTS
      REFERENCING OLD AS OLD
      FOR EACH ROW
      DELETE FROM FLIGHTAVAILABILITY WHERE FLIGHT_ID = OLD.FLIGHT_ID;

Note: You can find more examples in the Java DB Developer's Guide.
Trigger recursion
The maximum trigger recursion depth is 16.
Related information
Special system functions that return information about the current time or current user are evaluated when the trigger fires, not when it is created. Such functions include:

• |  | CURRENT_DATE function
• |  | CURRENT_TIME function
• |  | CURRENT_TIMESTAMP function
• |  | CURRENT_USER function
• |  | SESSION_USER function
• |  | USER function

ReferencingClause:

    REFERENCING
    {
    { OLD | NEW } [ AS ] correlation-Name [ { OLD | NEW } [ AS ] correlation-Name ] |
    { OLD_TABLE | NEW_TABLE } [ AS ] Identifier [ { OLD_TABLE | NEW_TABLE }
    [AS] Identifier ]
    }

CREATE VIEW statement
Views are virtual tables formed by a query. A view is a dictionary object that you can use until you drop it. Views are not updatable.
If a qualified view name is specified, the schema name cannot begin with SYS.
The view owner automatically gains the SELECT privilege on the view. The SELECT privilege cannot be revoked from the view owner. The database owner automatically gains the SELECT privilege on the view and is able to grant this privilege to other users. The SELECT privilege cannot be revoked from the database owner.
The view owner can only grant the SELECT privilege to other users if the view owner also owns the underlying objects.
If the underlying objects that the view references are not owned by the view owner, the view owner must be granted the appropriate privileges. For example, if the authorization ID user2 attempts to create a view called user2.v2 that references table user1.t1 and function user1.f_abs(), then user2 must have the SELECT privilege on table user1.t1 and the EXECUTE privilege on function user1.f_abs().
The privilege to grant the SELECT privilege cannot be revoked. If a required privilege on one of the underlying objects that the view references is revoked, then the view is dropped.
Syntax

    CREATE VIEW view-Name
        [ ( Simple-column-Name [, Simple-column-Name] * ) ]
    AS Query

A view definition can contain an optional view column list to explicitly name the columns in the view. If there is no column list, the view inherits the column names from the underlying query. All columns in a view must be uniquely named.

    CREATE VIEW SAMP.V1 (COL_SUM, COL_DIFF)
    	AS SELECT COMM + BONUS, COMM - BONUS
    	FROM SAMP.EMPLOYEE;

    CREATE VIEW SAMP.VEMP_RES (RESUME)
    	AS VALUES 'Delores M. Quintana', 'Heather A. Nicholls', 'Bruce Adamson';

    CREATE VIEW SAMP.PROJ_COMBO
    	(PROJNO, PRENDATE, PRSTAFF, MAJPROJ)
    	AS SELECT PROJNO, PRENDATE, PRSTAFF, MAJPROJ
    	FROM SAMP.PROJECT UNION ALL
    SELECT PROJNO, EMSTDATE, EMPTIME, EMPNO
    	FROM SAMP.EMP_ACT
    	WHERE EMPNO IS NOT NULL;

Statement dependency system
View definitions are dependent on the tables and views referenced within the view definition. DML (data manipulation language) statements that contain view references depend on those views, as well as the objects in the view definitions that the views are dependent on. Statements that reference the view depend on indexes the view uses; which index a view uses can change from statement to statement based on how the query is optimized. For example, given:

    CREATE TABLE T1 (C1 DOUBLE PRECISION);

    CREATE FUNCTION SIN (DATA DOUBLE)
    	RETURNS DOUBLE EXTERNAL NAME 'java.lang.Math.sin'
    	LANGUAGE JAVA PARAMETER STYLE JAVA;

    CREATE VIEW V1 (C1) AS SELECT SIN(C1) FROM T1;

the following SELECT:

    SELECT * FROM V1

is dependent on view V1, table T1, and external scalar function SIN.
DECLARE GLOBAL TEMPORARY TABLE statement
The DECLARE GLOBAL TEMPORARY TABLE statement defines a temporary table for the current connection.
These tables do not reside in the system catalogs and are not persistent. Temporary tables exist only during the connection that declared them and cannot be referenced outside of that connection. When the connection closes, the rows of the table are deleted, and the in-memory description of the temporary table is dropped.
Temporary tables are useful when:

• |  | The table structure is not known before using an application.
• |  | Other users do not need the same table structure.
• |  | Data in the temporary table is needed while using the application.
• |  | The table can be declared and dropped without holding the locks on the system catalog.

Syntax

    DECLARE GLOBAL TEMPORARY TABLE table-Name
        { column-definition [ , column-definition ] * }
    [ ON COMMIT {DELETE | PRESERVE} ROWS ]
    NOT LOGGED [ON ROLLBACK DELETE ROWS]

table-Name
Names the temporary table. If a schema-Name other than SESSION is specified, an error will occur (SQLSTATE 428EK). If the schema-Name is not specified, SESSION is assigned. Multiple connections can define declared global temporary tables with the same name because each connection has its own unique table descriptor for it.
Using SESSION as the schema name of a physical table will not cause an error, but is discouraged. The SESSION schema name should be reserved for the temporary table schema.
column-definition
See column-definition for CREATE TABLE for more information on column-definition. DECLARE GLOBAL TEMPORARY TABLE does not allow generated-column-spec in the column-definition.
Data type
Supported data types are:

• |  | BIGINT
• |  | CHAR
• |  | DATE
• |  | DECIMAL
• |  | DOUBLE
• |  | DOUBLE PRECISION
• |  | FLOAT
• |  | INTEGER
• |  | NUMERIC
• |  | REAL
• |  | SMALLINT
• |  | TIME
• |  | TIMESTAMP
• |  | VARCHAR

ON COMMIT
Specifies the action taken on the global temporary table when a COMMIT operation is performed.
DELETE ROWS
All rows of the table will be deleted if no hold-able cursor is open on the table. This is the default value for ON COMMIT. If you specify ON ROLLBACK DELETE ROWS, this will delete all the rows in the table only if the temporary table was used. ON COMMIT DELETE ROWS will delete the rows in the table even if the table was not used (if the table does not have hold-able cursors open on it).
PRESERVE ROWS
The rows of the table will be preserved.
NOT LOGGED
Specifies the action taken on the global temporary table when a rollback operation is performed. When a ROLLBACK (or ROLLBACK TO SAVEPOINT) operation is performed, if the table was created in the unit of work (or savepoint), the table will be dropped. If the table was dropped in the unit of work (or savepoint), the table will be restored with no rows.
ON ROLLBACK DELETE ROWS
This is the default value for NOT LOGGED. NOT LOGGED [ON ROLLBACK DELETE ROWS ]] specifies the action that is to be taken on the global temporary table when a ROLLBACK or (ROLLBACK TO SAVEPOINT) operation is performed. If the table data has been changed, all the rows will be deleted.
Examples

    set schema myapp;

    create table t1(c11 int, c12 date);

    declare global temporary table SESSION.t1(c11 int) not logged;
    -- The SESSION qualification is redundant here because temporary
    -- tables can only exist in the SESSION schema.

    declare global temporary table t2(c21 int) not logged;
    -- The temporary table is not qualified here with SESSION because temporary
    -- tables can only exist in the SESSION schema.

    insert into SESSION.t1 values (1);
    -- SESSION qualification is mandatory here if you want to use
    -- the temporary table, because the current schema is "myapp."

    select * from t1;
    -- This select statement is referencing the "myapp.t1" physical
    -- table since the table was not qualified by SESSION.

Note: Temporary tables can be declared only in the SESSION schema. You should never declare a physical schema with the SESSION name.
The following is a list of DB2 UDB DECLARE GLOBAL TEMPORARY TABLE functions that are not supported by Derby:

• |  | IDENTITY column-options
• |  | IDENTITY attribute in copy-options
• |  | AS (fullselect) DEFINITION ONLY
• |  | NOT LOGGED ON ROLLBACK PRESERVE ROWS
• |  | IN tablespace-name
• |  | PARTITIONING KEY
• |  | WITH REPLACE

Restrictions on Declared Global Temporary Tables
Derby does not support the following features on temporary tables. Some of these features are specific to temporary tables and some are specific to Derby.
Temporary tables cannot be specified in the following statements:

• |  | ALTER TABLE
• |  | CREATE INDEX
• |  | CREATE SYNONYM
• |  | CREATE TRIGGER
• |  | CREATE VIEW
• |  | GRANT
• |  | LOCK TABLE
• |  | RENAME
• |  | REVOKE

You cannot use the following features with temporary tables:

• |  | Synonyms, triggers and views on SESSION schema tables (including physical tables and temporary tables)
• |  | Caching statements that reference SESSION schema tables and views
• |  | Temporary tables cannot be specified in referential constraints and primary keys
• |  | Temporary tables cannot be referenced in a triggered-SQL-statement
• |  | Check constraints on columns
• |  | Generated-column-spec
• |  | Importing into temporary tables

If a statement that performs an insert, update, or delete to the temporary table encounters an error, all the rows of the temporary table are deleted.
The following data types cannot be used with Declared Global Temporary Tables:

• |  | BLOB
• |  | CHAR FOR BIT DATA
• |  | CLOB
• |  | LONG VARCHAR
• |  | LONG VARCHAR FOR BIT DATA
• |  | VARCHAR FOR BIT DATA
• |  | XML

DELETE statement
Syntax

    {
        DELETE FROM table-Name
            [WHERE clause] |
        DELETE FROM table-Name WHERE CURRENT OF
    }

The first syntactical form, called a searched delete, removes all rows identified by the table name and WHERE clause.
The second syntactical form, called a positioned delete, deletes the current row of an open, updatable cursor. For more information about updatable cursors, see SELECT statement.
Examples

    DELETE FROM SAMP.IN_TRAY

    stmt.executeUpdate("DELETE FROM SAMP.IN_TRAY WHERE CURRENT OF " +
    	resultSet.getCursorName());

Statement dependency system
A searched delete statement depends on the table being updated, all of its conglomerates (units of storage such as heaps or indexes), and any other table named in the WHERE clause. A CREATE or DROP INDEX statement for the target table of a prepared searched delete statement invalidates the prepared searched delete statement.
The positioned delete statement depends on the cursor and any tables the cursor references. You can compile a positioned delete even if the cursor has not been opened yet. However, removing the open cursor with the JDBC close method invalidates the positioned delete.
A CREATE or DROP INDEX statement for the target table of a prepared positioned delete invalidates the prepared positioned delete statement.
DROP statements
Use Drop statements with functions, indexes, procedures, schemas, synonyms, tables, triggers, and views.
DROP FUNCTION statement
Syntax

    DROP FUNCTION function-name

Identifies the particular function to be dropped, and is valid only if there is exactly one function instance with the function-name in the schema. The identified function can have any number of parameters defined for it. If no function with the indicated name in the named or implied schema, an error (SQLSTATE 42704) will occur. An error will also occur if there is more than one specific instance of the function in the named or implied schema.
DROP INDEX statement
DROP INDEX removes the specified index.
Syntax

    DROP INDEX index-Name

    DROP INDEX OrigIndex

    DROP INDEX DestIndex

Statement dependency system
If there is an open cursor on the table from which the index is dropped, the DROP INDEX statement generates an error and does not drop the index. Otherwise, statements that depend on the index's table are invalidated.
DROP PROCEDURE statement
Syntax

    DROP PROCEDURE procedure-Name

Identifies the particular procedure to be dropped, and is valid only if there is exactly one procedure instance with the procedure-name in the schema. The identified procedure can have any number of parameters defined for it. If no procedure with the indicated name in the named or implied schema, an error (SQLSTATE 42704) will occur. An error will also occur if there is more than one specific instance of the procedure in the named or implied schema.
DROP SCHEMA statement
The DROP SCHEMA statement drops a schema. The target schema must be empty for the drop to succeed.
Neither the APP schema (the default user schema) nor the SYS schema can be dropped.
Syntax

    DROP SCHEMA schemaName RESTRICT

The RESTRICT keyword enforces the rule that no objects can be defined in the specified schema for the schema to be deleted from the database. The RESTRICT keyword is required

    -- Drop the SAMP schema
    -- The SAMP schema may only be deleted from the database
    -- if no objects are defined in the SAMP schema.

    DROP SCHEMA SAMP RESTRICT

DROP SYNONYM statement
Drops the specified synonym from a table or view.
Syntax

    DROP SYNONYM synonym-Name

DROP TABLE statement
DROP TABLE removes the specified table.
Syntax

    DROP TABLE table-Name

Statement dependency system
Triggers, constraints (primary, unique, check and references from the table being dropped) and indexes on the table are silently dropped. The existence of an open cursor that references table being dropped cause the DROP TABLE statement to generate an error, and the table is not dropped.
Dropping a table invalidates statements that depend on the table. (Invalidating a statement causes it to be recompiled upon the next execution. See Interaction with the dependency system.)
DROP TRIGGER statement
DROP TRIGGER removes the specified trigger.
Syntax

    DROP TRIGGER TriggerName

    DROP TRIGGER TRIG1

Statement dependency system
When a table is dropped, all triggers on that table are automatically dropped. (You don't have to drop a table's triggers before dropping the table.)
DROP VIEW statement
Drops the specified view.
Syntax

    DROP VIEW view-Name

    DROP VIEW AnIdentifier

Statement dependency system
Any statements referencing the view are invalidated on a DROP VIEW statement. DROP VIEW is disallowed if there are any views or open cursors dependent on the view. The view must be dropped before any objects that it is dependent on can be dropped.
GRANT statement
Use the GRANT statement to give permissions to a specific user or all users to perform actions on database objects.
The following types of permissions can be granted:

• |  | Delete data from a specific table.
• |  | Insert data into a specific table.
• |  | Create a foreign key reference to the named table or to a subset of columns from a table.
• |  | Select data from a table, view, or a subset of columns in a table.
• |  | Create a trigger on a table.
• |  | Update data in a table or in a subset of columns in a table.
• |  | Run a specified function or procedure.

Before you issue a GRANT statement, check that the derby.database.sqlAuthorization property is set to true. The derby.database.sqlAuthorization property enables the SQL Authorization mode.
You can grant privileges to database objects that you are authorized to grant. See the CREATE statement for the database object that you want to grant privileges on for more information.
The syntax that you use for the GRANT statement depends on whether you are granting privileges to a table or to a routine.
Syntax for tables

    GRANT privilege-type ON [TABLE] { table-Name | view-Name } TO grantees

Syntax for routines

    GRANT EXECUTE ON { FUNCTION | PROCEDURE } routine-designator TO grantees

privilege-type

      {
    	ALL PRIVILEGES |
    	DELETE |
    	INSERT |
    	REFERENCES [column list] |
     	SELECT [column list] |
    	TRIGGER |
    	UPDATE [column list}
      }

Use the DELETE privilege type to grant permission to delete rows from the specified table.
Use the INSERT privilege type to grant permission to insert rows into the specified table.
Use the REFERENCES privilege type to grant permission to create a foreign key reference to the specified table. If a column list is specified with the REFERENCES privilege, the permission is valid on only the foreign key reference to the specified columns.
Use the SELECT privilege type to grant permission to perform SELECT statements on a table or view. If a column list is specified with the SELECT privilege, the permission is valid on only those columns. If no column list is specified, then the privilege is valid on all of the columns in the table.
Use the TRIGGER privilege type to grant permission to create a trigger on the specified table.
Use the UPDATE privilege type to grant permission to use the UPDATE statement on the specified table. If a column list is specified, the permission applies only to the specified columns. To update a row using a statement that includes a WHERE clause, you must have SELECT permission on the columns in the row that you want to update.
grantees

    {	authorization ID | PUBLIC } [,{ authorization ID | PUBLIC } ] *

You can grant privileges for specific users or for all users. Use the keyword PUBLIC to specify all users. When PUBLIC is specified, the privileges affect all current and future users. The privileges granted to PUBLIC and to individual users are independent privileges. For example, a SELECT privilege on table t is granted to both PUBLIC and to the authorization ID harry. The SELECT privilege is later revoked from the authorization ID harry, but Harry can access the table t through the PUBLIC privilege.
routine-designator

    {
    	function-name | procedure-name
    }

Examples
To grant the SELECT privilege on table t to the authorization IDs maria and harry, use the following syntax:

    GRANT SELECT ON TABLE t TO maria,harry

To grant the UPDATE and TRIGGER privileges on table t to the authorization IDs anita and zhi, use the following syntax:

    GRANT UPDATE, TRIGGER ON TABLE t TO anita,zhi

To grant the SELECT privilege on table s.v to all users, use the following syntax:

    GRANT SELECT ON TABLE s.v to PUBLIC

To grant the EXECUTE privilege on procedure p to the authorization ID george, use the following syntax:

    GRANT EXECUTE ON PROCEDURE p TO george

INSERT statement
An INSERT statement creates a row or rows and stores them in the named table. The number of values assigned in an INSERT statement must be the same as the number of specified or implied columns.
Syntax

    INSERT INTO table-Name
        [ (Simple-column-Name [ , Simple-column-Name]* ) ]
    	  Query

Query can be:

• |  | a SelectExpression
• |  | a VALUES list
• |  | a multiple-row VALUES expression Single-row and multiple-row lists can include the keyword DEFAULT. Specifying DEFAULT for a column inserts the column's default value into the column. Another way to insert the default value into the column is to omit the column from the column list and only insert values into other columns in the table. For more information see VALUES Expression.
• |  | UNION expressions

For more information about Query, see Query.

    INSERT INTO COUNTRIES
          VALUES ('Taiwan', 'TW', 'Asia')

    -- Insert a new department into the DEPARTMENT table,
    -- but do not assign a manager to the new department
    INSERT INTO DEPARTMENT (DEPTNO, DEPTNAME, ADMRDEPT)
    	VALUES ('E31', 'ARCHITECTURE', 'E01')
    -- Insert two new departments using one statement
    -- into the DEPARTMENT table as in the previous example,
    -- but do not assign a manager to the new department.
    INSERT INTO DEPARTMENT (DEPTNO, DEPTNAME, ADMRDEPT)
    	VALUES ('B11', 'PURCHASING', 'B01'),
    	('E41', 'DATABASE ADMINISTRATION', 'E01')
    --  Create a temporary table MA_EMP_ACT with the
    -- same columns as the EMP_ACT table.
    -- Load MA_EMP_ACT with the rows from the EMP_ACT
    -- table with a project number (PROJNO)
    -- starting with the letters 'MA'.
    CREATE TABLE MA_EMP_ACT
        (
    	EMPNO CHAR(6)  NOT NULL,
    	PROJNO CHAR(6)  NOT NULL,
    	ACTNO SMALLINT  NOT NULL,
    	EMPTIME DEC(5,2),
    	EMSTDATE DATE,
    	EMENDATE  DATE
        );

    INSERT INTO MA_EMP_ACT
    	SELECT * FROM EMP_ACT
    	WHERE SUBSTR(PROJNO, 1, 2) = 'MA';
    -- Insert the DEFAULT value for the LOCATION column
    INSERT INTO DEPARTMENT
          VALUES ('E31', 'ARCHITECTURE', '00390', 'E01', DEFAULT)

Statement dependency system
The INSERT statement depends on the table being inserted into, all of the conglomerates (units of storage such as heaps or indexes) for that table, and any other table named in the statement. Any statement that creates or drops an index or a constraint for the target table of a prepared INSERT statement invalidates the prepared INSERT statement.
LOCK TABLE statement
The LOCK TABLE statement allows you to explicitly acquire a shared or exclusive table lock on the specified table. The table lock lasts until the end of the current transaction.
To lock a table, you must either be the database owner or the table owner.
Explicitly locking a table is useful to:

• |  | Avoid the overhead of multiple row locks on a table (in other words, user-initiated lock escalation)
• |  | Avoid deadlocks

You cannot lock system tables with this statement.
Syntax

    LOCK TABLE table-Name IN { SHARE | EXCLUSIVE } MODE

After a table is locked in either mode, a transaction does not acquire any subsequent row-level locks on a table. For example, if a transaction locks the entire Flights table in share mode in order to read data, a particular statement might need to lock a particular row in exclusive mode in order to update the row. However, the previous table-level lock on the Flights table forces the exclusive lock to be table-level as well.
If the specified lock cannot be acquired because another connection already holds a lock on the table, a statement-level exception is raised (SQLState X0X02) after the deadlock timeout period.
Examples
To lock the entire Flights table in share mode to avoid a large number of row locks, use the following statement:

    LOCK TABLE Flights IN SHARE MODE;
    SELECT *
    FROM Flights
    WHERE orig_airport > 'OOO';

You have a transaction with multiple UPDATE statements. Since each of the individual statements acquires only a few row-level locks, the transaction will not automatically upgrade the locks to a table-level lock. However, collectively the UPDATE statements acquire and release a large number of locks, which might result in deadlocks. For this type of transaction, you can acquire an exclusive table-level lock at the beginning of the transaction. For example:

    LOCK TABLE FlightAvailability IN EXCLUSIVE MODE;
    UPDATE FlightAvailability
    SET economy_seats_taken = (economy_seats_taken + 2)
    WHERE flight_id = 'AA1265' AND flight_date = DATE('2004-03-31');

    UPDATE FlightAvailability
    SET economy_seats_taken = (economy_seats_taken + 2)
    WHERE flight_id = 'AA1265' AND flight_date = DATE('2004-04-11');

    UPDATE FlightAvailability
    SET economy_seats_taken = (economy_seats_taken + 2)
    WHERE flight_id = 'AA1265' AND flight_date = DATE('2004-04-12');

    UPDATE FlightAvailability
    SET economy_seats_taken = (economy_seats_taken + 2)
    WHERE flight_id = 'AA1265' AND flight_date = DATE('2004-04-15');

If a transaction needs to look at a table before updating the table, acquire an exclusive lock before selecting to avoid deadlocks. For example:

    LOCK TABLE Maps IN EXCLUSIVE MODE;
    SELECT MAX(map_id) + 1 FROM Maps;
    -- INSERT INTO Maps . . .

RENAME statements
Use the Rename statements with indexes, columns, and tables.
RENAME COLUMN statement
Use the RENAME COLUMN statement to rename a column in a table.
The RENAME COLUMN statement allows you to rename an existing column in an existing table in any schema (except the schema SYS).
To rename a column, you must either be the database owner or the table owner.
Other types of table alterations are possible; see ALTER TABLE statement for more information.
Syntax

    RENAME COLUMN table-Name.simple-Column-Name TO simple-Column-Name

Examples
To rename the manager column in table employee to supervisor, use the following syntax:

    RENAME COLUMN EMPLOYEE.MANAGER TO SUPERVISOR

You can combine ALTER TABLE and RENAME COLUMN to modify a column's data type. To change column c1 of table t to the new data type NEWTYPE:

        ALTER TABLE t ADD COLUMN c1_newtype NEWTYPE
        UPDATE t SET c1_newtype = c1
        ALTER TABLE t DROP COLUMN c1
        RENAME COLUMN t.c1_newtype TO c1

Usage notes
Note: If there is a view, trigger, check constraint, or foreign key constraint that references the column, attempts to rename it will generate an error.
Note: The RENAME COLUMN statement is not allowed if there are any open cursors that reference the column that is being altered.
Note: If there is an index defined on the column, the column can still be renamed; the index is automatically updated to refer to the column by its new name
RENAME INDEX statement
This statement allows you to rename an index in the current schema. Users cannot rename indexes in the SYS schema.
Syntax

    RENAME INDEX index-Name TO new-index-Name

    RENAME INDEX DESTINDEX TO ARRIVALINDEX

Statement dependency system
RENAME INDEX is not allowed if there are any open cursors that reference the index being renamed.
RENAME TABLE statement
RENAME TABLE allows you to rename an existing table in any schema (except the schema SYS).
To rename a table, you must either be the database owner or the table owner.
Syntax

    RENAME TABLE table-Name TO new-Table-Name

If there is a view or foreign key that references the table, attempts to rename it will generate an error. In addition, if there are any check constraints or triggers on the table, attempts to rename it will also generate an error.

    RENAME TABLE SAMP.EMP_ACT TO EMPLOYEE_ACT

Also see ALTER TABLE statement for more information.
Statement dependency system
If there is an index defined on the table, the table can be renamed.
The RENAME TABLE statement is not allowed if there are any open cursors that reference the table that is being altered.
REVOKE statement
Use the REVOKE statement to remove permissions from a specific user or from all users to perform actions on database objects.
The following types of permissions can be revoked:

• |  | Delete data from a specific table.
• |  | Insert data into a specific table.
• |  | Create a foreign key reference to the named table or to a subset of columns from a table.
• |  | Select data from a table, view, or a subset of columns in a table.
• |  | Create a trigger on a table.
• |  | Update data in a table or in a subset of columns in a table.
• |  | Run a specified routine (function or procedure).

Before you issue a REVOKE statement, check that the derby.database.sqlAuthorization property is set to true. The derby.database.sqlAuthorization property enables the SQL Authorization mode.
You can revoke privileges from an object if you are the owner of the object or the database owner.
The syntax that you use for the REVOKE statement depends on whether you are revoking privileges to a table or to a routine.
Syntax for tables

    REVOKE privilege-type ON [ TABLE ] { table-Name | view-Name } FROM grantees

Revoking a privilege without specifying a column list revokes the privilege for all of the columns in the table.
Syntax for routines

    REVOKE EXECUTE ON { FUNCTION | PROCEDURE } routine-designator FROM grantees RESTRICT

You must use the RESTRICT clause on REVOKE statements for routines. The RESTRICT clause specifies that the EXECUTE privilege cannot be revoked if the specified routine is used in a view, trigger, or constraint, and the privilege is being revoked from the owner of the view, trigger, or constraint.
privilege-type

      {
    	ALL PRIVILEGES |
    	DELETE |
    	INSERT |
    	REFERENCES [column list] |
     	SELECT [column list] |
    	TRIGGER |
    	UPDATE [column list}
     }

Use the ALL PRIVILEGES privilege type to revoke all of the permissions from the user for the specified table.
Use the DELETE privilege type to revoke permission to delete rows from the specified table.
Use the INSERT privilege type to revoke permission to insert rows into the specified table.
Use the REFERENCES privilege type to revoke permission to create a foreign key reference to the specified table. If a column list is specified with the REFERENCES privilege, the permission is revoked on only the foreign key reference to the specified columns.
Use the SELECT privilege type to revoke permission to perform SELECT statements on a table or view. If a column list is specified with the SELECT privilege, the permission is revoked on only those columns. If no column list is specified, then the privilege is valid on all of the columns in the table.
Use the TRIGGER privilege type to revoke permission to create a trigger on the specified table.
Use the UPDATE privilege type to revoke permission to use the UPDATE statement on the specified table. If a column list is specified, the permission is revoked only on the specified columns.
grantees

    {	authorization ID | PUBLIC } [,{ authorization ID | PUBLIC } ] *

You can revoke the privileges from specific users or from all users. Use the keyword PUBLIC to specify all users. The privileges revoked from PUBLIC and from individual users are independent privileges. For example, a SELECT privilege on table t is granted to both PUBLIC and to the authorization ID harry. The SELECT privilege is later revoked from the authorization ID harry, but the authorization ID harry can access the table t through the PUBLIC privilege.
Restriction: You cannot revoke the privileges of the owner of an object.
routine-designator

      {
    		qualified-name [ signature ]
      }

Cascading object dependencies
For views, triggers, and constraints, if the privilege on which the object depends on is revoked, the object is automatically dropped. Derby does not try to determine if you have other privileges that can replace the privileges that are being revoked. For more information, see "SQL standard authorization" in the Java DB Developer's Guide.
Limitations
The following limitations apply to the REVOKE statement:
Table-level privileges
All of the table-level privilege types for a specified grantee and table ID are stored in one row in the SYSTABLEPERMS system table. For example, when user2 is granted the SELECT and DELETE privileges on table user1.t1, a row is added to the SYSTABLEPERMS table. The GRANTEE field contains user2 and the TABLEID contains user1.t1. The SELECTPRIV and DELETEPRIV fields are set to Y. The remaining privilege type fields are set to N.
When a grantee creates an object that relies on one of the privilege types, the Derby engine tracks the dependency of the object on the specific row in the SYSTABLEPERMS table. For example, user2 creates the view v1 by using the statement SELECT * FROM user1.t1, the dependency manager tracks the dependency of view v1 on the row in SYSTABLEPERMS for GRANTEE(user2), TABLEID(user1.t1). The dependency manager knows only that the view is dependent on a privilege type in that specific row, but does not track exactly which privilege type the view is dependent on.
When a REVOKE statement for a table-level privilege is issued for a grantee and table ID, all of the objects that are dependent on the grantee and table ID are dropped. For example, if user1 revokes the DELETE privilege on table t1 from user2, the row in SYSTABLEPERMS for GRANTEE(user2), TABLEID(user1.t1) is modified by the REVOKE statement. The dependency manager sends a revoke invalidation message to the view user2.v1 and the view is dropped even though the view is not dependent on the DELETE privilege for GRANTEE(user2), TABLEID(user1.t1).
Column-level privileges
Only one type of privilege for a specified grantee and table ID are stored in one row in the SYSCOLPERMS system table. For example, when user2 is granted the SELECT privilege on table user1.t1 for columns c12 and c13, a row is added to the SYSCOLPERMS. The GRANTEE field contains user2, the TABLEID contains user1.t1, the TYPE field contains S, and the COLUMNS field contains c12, c13.
When a grantee creates an object that relies on the privilege type and the subset of columns in a table ID, the Derby engine tracks the dependency of the object on the specific row in the SYSCOLPERMS table. For example, user2 creates the view v1 by using the statement SELECT c11 FROM user1.t1, the dependency manager tracks the dependency of view v1 on the row in SYSCOLPERMS for GRANTEE(user2), TABLEID(user1.t1), TYPE(S). The dependency manager knows that the view is dependent on the SELECT privilege type, but does not track exactly which columns the view is dependent on.
When a REVOKE statement for a column-level privilege is issued for a grantee, table ID, and type, all of the objects that are dependent on the grantee, table ID, and type are dropped. For example, if user1 revokes the SELECT privilege on column c12 on table user1.t1 from user2, the row in SYSCOLPERMS for GRANTEE(user2), TABLEID(user1.t1), TYPE(S) is modified by the REVOKE statement. The dependency manager sends a revoke invalidation message to the view user2.v1 and the view is dropped even though the view is not dependent on the column c12 for GRANTEE(user2), TABLEID(user1.t1), TYPE(S).
Revoke examples
To revoke the SELECT privilege on table t from the authorization IDs maria and harry, use the following syntax:

    REVOKE SELECT ON TABLE t FROM maria,harry

To revoke the UPDATE and TRIGGER privileges on table t from the authorization IDs anita and zhi, use the following syntax:

    REVOKE UPDATE, TRIGGER ON TABLE t FROM anita,zhi

To revoke the SELECT privilege on table s.v from all users, use the following syntax:

    REVOKE SELECT ON TABLE s.v FROM PUBLIC

To revoke the UPDATE privilege on columns c1 and c2 of table s.v from all users, use the following syntax:

    REVOKE UPDATE (c1,c2) ON TABLE s.v FROM PUBLIC

To revoke the EXECUTE privilege on procedure p from the authorization ID george, use the following syntax:

    REVOKE EXECUTE ON PROCEDURE p FROM george RESTRICT

SET statements
Use the Set statements with schemas and to set the current isolation level.
SET ISOLATION statement
The SET ISOLATION statement allows a user to change the isolation level for the user's connection. Valid levels are SERIALIZABLE, REPEATABLE READ, READ COMMITTED, and READ UNCOMMITTED.
Issuing this statement always commits the current transaction. The JDBC java.sql.Connection.setTransactionIsolation method behaves almost identically to this command, with one exception: if you are using the embedded driver, and if the call to java.sql.Connection.setTransactionIsolation does not actually change the isolation level (that is, if it sets the isolation level to its current value), the current transaction is not committed.
For information about isolation levels, see "Locking, concurrency, and isolation" in the Java DB Developer's Guide. For information about the JDBC java.sql.Connection.setTransactionIsolation method, see java.sql.Connection.setTransactionIsolation method.
Syntax

    SET [ CURRENT ] ISOLATION [ = ]
    {
    UR | DIRTY READ | READ UNCOMMITTED
    CS | READ COMMITTED | CURSOR STABILITY
    RS |
    RR | REPEATABLE READ | SERIALIZABLE
    RESET
    }

    set isolation serializable;

SET SCHEMA statement
The SET SCHEMA statement sets the default schema for a connection's session to the designated schema. The default schema is used as the target schema for all statements issued from the connection that do not explicitly specify a schema name.
The target schema must exist for the SET SCHEMA statement to succeed. If the schema doesn't exist an error is returned. See CREATE SCHEMA statement.
The SET SCHEMA statement is not transactional: If the SET SCHEMA statement is part of a transaction that is rolled back, the schema change remains in effect.
Syntax

    SET [CURRENT] SCHEMA [=]
    { schemaName|
    USER | ? | '<string-constant>' } | SET CURRENT SQLID [=]
    {
    schemaName| USER | ? | '<string-constant>' }

schemaName is an identifier with a maximum length of 128. It is case insensitive unless enclosed in double quotes. (For example, SYS is equivalent to sYs, SYs, sys, etcetera.)
USER is the current user. If no current user is defined, the current schema defaults the APP schema. (If a user name was specified upon connection, the user's name is the default schema for the connection, if a schema with that name exists.)
? is a dynamic parameter specification that can be used in prepared statements. The SET SCHEMA statement can be prepared once and then executed with different schema values. The schema values are treated as string constants so they are case sensitive. For example, to designate the APP schema, use the string "APP" rather than "app".

    -- the following are all equivalent and will work
    -- assuming a schema called HOTEL
    SET SCHEMA HOTEL
    SET SCHEMA hotel
    SET CURRENT SCHEMA hotel
    SET CURRENT SQLID hotel
    SET SCHEMA = hotel
    SET CURRENT SCHEMA = hotel
    SET CURRENT SQLID = hotel
    SET SCHEMA "HOTEL" -- quoted identifier
    SET SCHEMA 'HOTEL' -- quoted string--This example produces an error because
     --lower case hotel won't be found
    SET SCHEMA = 'hotel'
     --This example produces an error because SQLID is not
     --allowed without CURRENT
    SET SQLID hotel
     -- This sets the schema to the current user id
    SET CURRENT SCHEMA USER
    // Here's an example of using set schema in an Java program
    PreparedStatement ps = conn.PrepareStatement("set schema ?");
    ps.setString(1,"HOTEL");
    ps.executeUpdate();
    ... do some work
    ps.setString(1,"APP");
    ps.executeUpdate();

    ps.setString(1,"app"); //error - string is case sensitive
    // no app will be found
    ps.setNull(1, Types.VARCHAR); //error - null is not allowed

SELECT statement
Syntax

    Query
    [ORDER BY clause]
    [FOR UPDATE clause]
    WITH {RR|RS|CS|UR}

A SELECT statement consists of a query with an optional ORDER BY clause and an optional FOR UPDATE clause. The SELECT statement is so named because the typical first word of the query construct is SELECT. (Query includes the VALUES expression and UNION, INTERSECT, and EXCEPT expressions as well as SELECT expressions).
The ORDER BY clause guarantees the ordering of the ResultSet. The FOR UPDATE clause makes the result set's cursor updatable. The SELECT statement supports the FOR FETCH ONLY clause. The FOR FETCH ONLY clause is synonymous with the FOR READ ONLY clause.
You can set the isolation level in a SELECT statement using the WITH {RR|RS|CS|UR} syntax.
Example

    -- lists the names of the expression
    -- SAL+BONUS+COMM as TOTAL_PAY and
    -- orders by the new name TOTAL_PAY
    SELECT FIRSTNME, SALARY+BONUS+COMM AS TOTAL_PAY
         FROM EMPLOYEE
         ORDER BY TOTAL_PAY
    -- creating an updatable cursor with a FOR UPDATE clause
    -- to update the start date (PRSTDATE) and the end date (PRENDATE)
    -- columns in the PROJECT table
    SELECT PROJNO, PRSTDATE, PRENDATE
          FROM PROJECT
          FOR UPDATE OF PRSTDATE, PRENDATE
    -- set the isolation level to RR for this statement only
    SELECT *
    FROM Flights
    WHERE flight_id BETWEEN 'AA1111' AND 'AA1112'
    WITH RR

A SELECT statement returns a ResultSet. A cursor is a pointer to a specific row in ResultSet. In Java applications, all ResultSets have an underlying associated SQL cursor, often referred to as the result set's cursor. The cursor can be updatable, that is, you can update or delete rows as you step through the ResultSet if the SELECT statement that generated it and its underlying query meet cursor updatability requirements, as detailed below. The FOR UPDATE clause can be used to ensure a compilation check that the SELECT statement meets the requiremments of a updatable cursors, or to limit the columns that can be updated.
Note: The ORDER BY clause allows you to order the results of the SELECT. Without the ORDER BY clause, the results are returned in random order.
Requirements for updatable cursors and updatable ResultSets
Only simple, single-table SELECT cursors can be updatable. The SELECT statement for updatable ResultSets has the same syntax as the SELECT statement for updatable cursors. To generate updatable cursors:

• |  | The SELECT statement must not include an ORDER BY clause.
• |  | The underlying Query must be a SelectExpression.
• |  | The SelectExpression in the underlying Query must not include:
• |  | DISTINCT
• |  | Aggregates
• |  | GROUP BY clause
• |  | HAVING clause
• |  | ORDER BY clause
• |  | The FROM clause in the underlying Query must not have:
• |  | more than one table in its FROM clause
• |  | anything other than one table name
• |  | SelectExpressions
• |  | subqueries

Note: Cursors are read-only by default. To produce an updatable cursor besides meeting the requirements listed above, the concurrency mode for the ResultSet must be ResultSet.CONCUR_UPDATABLE or the SELECT statement must have FOR UPDATE in the FOR clause (see FOR UPDATE clause).
There is no SQL language statement to assign a name to a cursor. Instead, one can use the JDBC API to assign names to cursors or retrieve system-generated names. For more information, see Naming or accessing the name of a cursor in the Java DB Developer's Guide.
Statement dependency system
The SELECT depends on all the tables and views named in the query and the conglomerates (units of storage such as heaps and indexes) chosen for access paths on those tables. CREATE INDEX does not invalidate a prepared SELECT statement. A DROP INDEX statement invalidates a prepared SELECT statement if the index is an access path in the statement. If the SELECT includes views, it also depends on the dictionary objects on which the view itself depends (see CREATE VIEW statement).
Any prepared UPDATE WHERE CURRENT or DELETE WHERE CURRENT statement against a cursor of a SELECT depends on the SELECT. Removing a SELECT through a java.sql.Statement.close request invalidates the UPDATE WHERE CURRENT or DELETE WHERE CURRENT.
The SELECT depends on all aliases used in the query. Dropping an alias invalidates a prepared SELECT statement if the statement uses the alias.
UPDATE statement
Syntax

    {
        UPDATE table-Name
            SET column-Name = Value
            [ , column-Name = Value} ]*
            [WHERE clause] |
        UPDATE table-Name
            SET column-Name = Value
            [ , column-Name = Value ]*
            WHERE CURRENT OF
    }

where Value is defined as follows:

    Expression | DEFAULT

The first syntactical form, called a searched update, updates the value of one or more columns for all rows of the table for which the WHERE clause evaluates to TRUE.
The second syntactical form, called a positioned update, updates one or more columns on the current row of an open, updatable cursor. If columns were specified in the FOR UPDATE clause of the SELECT statement used to generate the cursor, only those columns can be updated. If no columns were specified or the select statement did not include a FOR UPDATE clause, all columns may be updated.
Specifying DEFAULT for the update value sets the value of the column to the default defined for that table.
Example

    -- All the employees except the manager of
    -- department (WORKDEPT) 'E21' have been temporarily reassigned.
    -- Indicate this by changing their job (JOB) to NULL and their pay
    -- (SALARY, BONUS, COMM) values to zero in the EMPLOYEE table.
    UPDATE EMPLOYEE
      SET JOB=NULL, SALARY=0, BONUS=0, COMM=0
      WHERE WORKDEPT = 'E21' AND JOB <> 'MANAGER'

    -- PROMOTE the job (JOB) of employees without a specific job title to MANAGER
    UPDATE EMPLOYEE
    	SET JOB = 'MANAGER'
    	WHERE JOB IS NULL;
    // Increase the project staffing (PRSTAFF) by 1.5 for all projects
    stmt.executeUpdate("UPDATE PROJECT SET PRSTAFF = "
    "PRSTAFF + 1.5" +
    "WHERE CURRENT OF" + ResultSet.getCursorName());

    -- Change the job (JOB) of employee number (EMPNO) '000290' in the EMPLOYEE table
    -- to its DEFAULT value which is NULL
    UPDATE EMPLOYEE
      SET JOB = DEFAULT
      WHERE EMPNO = '000290'

Statement dependency system
A searched update statement depends on the table being updated, all of its conglomerates (units of storage such as heaps or indexes), all of its constraints, and any other table named in the WHERE clause or SET expressions. A CREATE or DROP INDEX statement or an ALTER TABLE statement for the target table of a prepared searched update statement invalidates the prepared searched update statement.
The positioned update statement depends on the cursor and any tables the cursor references. You can compile a positioned update even if the cursor has not been opened yet. However, removing the open cursor with the JDBC close method invalidates the positioned update.
A CREATE or DROP INDEX statement or an ALTER TABLE statement for the target table of a prepared positioned update invalidates the prepared positioned update statement.
Dropping an alias invalidates a prepared update statement if the latter statement uses the alias.
Dropping or adding triggers on the target table of the update invalidates the update statement.
SQL clauses
CONSTRAINT clause
A CONSTRAINT clause is an optional part of a CREATE TABLE statement or ALTER TABLE statement. A constraint is a rule to which data must conform. Constraint names are optional.
A CONSTRAINT can be one of the following:

• |  | a column-level constraint Column-level constraints refer to a single column in the table and do not specify a column name (except check constraints). They refer to the column that they follow.
• |  | a table-level constraint Table-level constraints refer to one or more columns in the table. Table-level constraints specify the names of the columns to which they apply. Table-level CHECK constraints can refer to 0 or more columns in the table.

Column constraints include:

• |  | NOT NULL Specifies that this column cannot hold NULL values (constraints of this type are not nameable).
• |  | PRIMARY KEY Specifies the column that uniquely identifies a row in the table. The identified columns must be defined as NOT NULL. Note: If you attempt to add a primary key using ALTER TABLE and any of the columns included in the primary key contain null values, an error will be generated and the primary key will not be added. See ALTER TABLE statement for more information.
• |  | UNIQUE Specifies that values in the column must be unique. NULL values are not allowed.
• |  | FOREIGN KEY Specifies that the values in the column must correspond to values in a referenced primary key or unique key column or that they are NULL.
• |  | CHECK Specifies rules for values in the column.

Table constraints include:

• |  | PRIMARY KEY Specifies the column or columns that uniquely identify a row in the table. NULL values are not allowed.
• |  | UNIQUE Specifies that values in the columns must be unique. The identified columns must be defined as NOT NULL.
• |  | FOREIGN KEY Specifies that the values in the columns must correspond to values in referenced primary key or unique columns or that they are NULL. Note: If the foreign key consists of multiple columns, and any column is NULL, the whole key is considered NULL. The insert is permitted no matter what is on the non-null columns.
• |  | CHECK Specifies a wide range of rules for values in the table.

Column constraints and table constraints have the same function; the difference is in where you specify them. Table constraints allow you to specify more than one column in a PRIMARY KEY, UNIQUE, CHECK, or FOREIGN KEY constraint definition. Column-level constraints (except for check constraints) refer to only one column.
Syntax
Primary key and unique constraints
A primary key defines the set of columns that uniquely identifies rows in a table.
When you create a primary key constraint, none of the columns included in the primary key can have NULL constraints; that is, they must not permit NULL values.
ALTER TABLE ADD PRIMARY KEY allows you to include existing columns in a primary key if they were first defined as NOT NULL. NULL values are not allowed. If the column(s) contain NULL values, the system will not add the primary key constraint. See ALTER TABLE statement for more information.
A table can have at most one PRIMARY KEY constraint, but can have multiple UNIQUE constraints.
Foreign key constraints
Foreign keys provide a way to enforce the referential integrity of a database. A foreign key is a column or group of columns within a table that references a key in some other table (or sometimes, though rarely, the same table). The foreign key must always include the columns of which the types exactly match those in the referenced primary key or unique constraint.
For a table-level foreign key constraint in which you specify the columns in the table that make up the constraint, you cannot use the same column more than once.
If there is a column list in the ReferencesSpecification (a list of columns in the referenced table), it must correspond either to a unique constraint or to a primary key constraint in the referenced table. The ReferencesSpecification can omit the column list for the referenced table if that table has a declared primary key.
If there is no column list in the ReferencesSpecification and the referenced table has no primary key, a statement exception is thrown. (This means that if the referenced table has only unique keys, you must include a column list in the ReferencesSpecification.)
A foreign key constraint is satisfied if there is a matching value in the referenced unique or primary key column. If the foreign key consists of multiple columns, the foreign key value is considered NULL if any of its columns contains a NULL.
Note: It is possible for a foreign key consisting of multiple columns to allow one of the columns to contain a value for which there is no matching value in the referenced columns, per the SQL-92 standard. To avoid this situation, create NOT NULL constraints on all of the foreign key's columns.
Foreign key constraints and DML
When you insert into or update a table with an enabled foreign key constraint, Derby checks that the row does not violate the foreign key constraint by looking up the corresponding referenced key in the referenced table. If the constraint is not satisfied, Derby rejects the insert or update with a statement exception.
When you update or delete a row in a table with a referenced key (a primary or unique constraint referenced by a foreign key), Derby checks every foreign key constraint that references the key to make sure that the removal or modification of the row does not cause a constraint violation. If removal or modification of the row would cause a constraint violation, the update or delete is not permitted and Derby throws a statement exception.
Derby performs constraint checks at the time the statement is executed, not when the transaction commits.
Backing indexes
UNIQUE, PRIMARY KEY, and FOREIGN KEY constraints generate indexes that enforce or "back" the constraint (and are sometimes called backing indexes). UNIQUE and PRIMARY KEY constraints generate unique indexes. FOREIGN KEY constraints generate non-unique indexes. Therefore, if a column or set of columns has a UNIQUE, PRIMARY KEY, or FOREIGN KEY constraint on it, you do not need to create an index on those columns for performance. Derby has already created it for you. See Indexes and constraints.
These indexes are available to the optimizer for query optimization (see CREATE INDEX statement) and have system-generated names.
You cannot drop backing indexes with a DROP INDEX statement; you must drop the constraint or the table.
Check constraints
A check constraint can be used to specify a wide range of rules for the contents of a table. A search condition (which is a boolean expression) is specified for a check constraint. This search condition must be satisfied for all rows in the table. The search condition is applied to each row that is modified on an INSERT or UPDATE at the time of the row modification. The entire statement is aborted if any check constraint is violated.
Requirements for search condition
If a check constraint is specified as part of a column-definition, a column reference can only be made to the same column. Check constraints specified as part of a table definition can have column references identifying columns previously defined in the CREATE TABLE statement.
The search condition must always return the same value if applied to the same values. Thus, it cannot contain any of the following:

• |  | Dynamic parameters (?)
• |  | Date/Time Functions (CURRENT_DATE, CURRENT_TIME, CURRENT_TIMESTAMP)
• |  | Subqueries
• |  | User Functions (such as USER, SESSION_USER, CURRENT_USER)

Referential actions
You can specify an ON DELETE clause and/or an ON UPDATE clause, followed by the appropriate action (CASCADE, RESTRICT, SET NULL, or NO ACTION) when defining foreign keys. These clauses specify whether Derby should modify corresponding foreign key values or disallow the operation, to keep foreign key relationships intact when a primary key value is updated or deleted from a table.
You specify the update and delete rule of a referential constraint when you define the referential constraint.
The update rule applies when a row of either the parent or dependent table is updated. The choices are NO ACTION and RESTRICT.
When a value in a column of the parent table's primary key is updated and the update rule has been specified as RESTRICT, Derby checks dependent tables for foreign key constraints. If any row in a dependent table violates a foreign key constraint, the transaction is rolled back.
If the update rule is NO ACTION, Derby checks the dependent tables for foreign key constraints after all deletes have been executed but before triggers have been executed. If any row in a dependent table violates a foreign key constraint, the statement is rejected.
When a value in a column of the dependent table is updated, and that value is part of a foreign key, NO ACTION is the implicit update rule. NO ACTION means that if a foreign key is updated with a non-null value, the update value must match a value in the parent table's primary key when the update statement is completed. If the update does not match a value in the parent table's primary key, the statement is rejected.
The delete rule applies when a row of the parent table is deleted and that row has dependents in the dependent table of the referential constraint. If rows of the dependent table are deleted, the delete operation on the parent table is said to be propagated to the dependent table. If the dependent table is also a parent table, the action specified applies, in turn, to its dependents.
The choices are NO ACTION, RESTRICT, CASCADE, or SET NULL. SET NULL can be specified only if some column of the foreign key allows null values.
If the delete rule is:
NO ACTION, Derby checks the dependent tables for foreign key constraints after all deletes have been executed but before triggers have been executed. If any row in a dependent table violates a foreign key constraint, the statement is rejected.
RESTRICT, Derby checks dependent tables for foreign key constraints. If any row in a dependent table violates a foreign key constraint, the transaction is rolled back.
CASCADE, the delete operation is propagated to the dependent table (and that table's dependents, if applicable).
SET NULL, each nullable column of the dependent table's foreign key is set to null. (Again, if the dependent table also has dependent tables, nullable columns in those tables' foreign keys are also set to null.)
Each referential constraint in which a table is a parent has its own delete rule; all applicable delete rules are used to determine the result of a delete operation. Thus, a row cannot be deleted if it has dependents in a referential constraint with a delete rule of RESTRICT or NO ACTION. Similarly, a row cannot be deleted if the deletion cascades to any of its descendants that are dependents in a referential constraint with the delete rule of RESTRICT or NO ACTION.
Deleting a row from the parent table involves other tables. Any table involved in a delete operation on the parent table is said to be delete-connected to the parent table. The delete can affect rows of these tables in the following ways:

• |  | If the delete rule is RESTRICT or NO ACTION, a dependent table is involved in the operation but is not affected by the operation. (That is, Derby checks the values within the table, but does not delete any values.)
• |  | If the delete rule is SET NULL, a dependent table's rows can be updated when a row of the parent table is the object of a delete or propagated delete operation.
• |  | If the delete rule is CASCADE, a dependent table's rows can be deleted when a parent table is the object of a delete.
• |  | If the dependent table is also a parent table, the actions described in this list apply, in turn, to its dependents.

Examples

    -- column-level primary key constraint named OUT_TRAY_PK:
    CREATE TABLE SAMP.OUT_TRAY
    	(
    	SENT TIMESTAMP,
    	DESTINATION CHAR(8),
    	SUBJECT CHAR(64) NOT NULL CONSTRAINT OUT_TRAY_PK PRIMARY KEY,
    	NOTE_TEXT VARCHAR(3000)
       );

    -- the table-level primary key definition allows you to
    -- include two columns in the primary key definition:
    CREATE TABLE SAMP.SCHED
    	(
    	CLASS_CODE CHAR(7) NOT NULL,
    	DAY SMALLINT NOT NULL,
    	STARTING TIME,
    	ENDING TIME,
    	PRIMARY KEY (CLASS_CODE, DAY)
    	);

    -- Use a column-level constraint for an arithmetic check
    -- Use a table-level constraint
    -- to make sure that a employee's taxes does not
    -- exceed the bonus
    CREATE TABLE SAMP.EMP
    	(
    	EMPNO CHAR(6) NOT NULL CONSTRAINT EMP_PK PRIMARY KEY,
    	FIRSTNME CHAR(12) NOT NULL,
    	MIDINIT vARCHAR(12) NOT NULL,
    	LASTNAME VARCHAR(15) NOT NULL,
    	SALARY DECIMAL(9,2) CONSTRAINT SAL_CK CHECK (SALARY >= 10000),
    	BONUS DECIMAL(9,2),
    	TAX DECIMAL(9,2),
    	CONSTRAINT BONUS_CK CHECK (BONUS > TAX)
    	);

    -- use a check constraint to allow only appropriate
    -- abbreviations for the meals
    CREATE TABLE FLIGHTS
    	(
    	FLIGHT_ID CHAR(6) NOT NULL ,
    	SEGMENT_NUMBER INTEGER NOT NULL ,
    	ORIG_AIRPORT CHAR(3),
    	DEPART_TIME TIME,
    	DEST_AIRPORT CHAR(3),
    	ARRIVE_TIME TIME,
    	MEAL CHAR(1) CONSTRAINT MEAL_CONSTRAINT
    	CHECK (MEAL IN ('B', 'L', 'D', 'S')),
    	PRIMARY KEY (FLIGHT_ID, SEGMENT_NUMBER)
    	);

    CREATE TABLE METROPOLITAN
    	(
    	HOTEL_ID INT NOT NULL CONSTRAINT HOTELS_PK PRIMARY KEY,
    	HOTEL_NAME VARCHAR(40) NOT NULL,
    	CITY_ID INT CONSTRAINT METRO_FK REFERENCES CITIES
    	);

    -- create a table with a table-level primary key constraint
    -- and a table-level foreign key constraint
    CREATE TABLE FLTAVAIL
    	(
    	FLIGHT_ID CHAR(6) NOT NULL,
    	SEGMENT_NUMBER INT NOT NULL,
    	FLIGHT_DATE DATE NOT NULL,
    	ECONOMY_SEATS_TAKEN INT,
    	BUSINESS_SEATS_TAKEN INT,
    	FIRSTCLASS_SEATS_TAKEN INT,
    	CONSTRAINT FLTAVAIL_PK PRIMARY KEY (FLIGHT_ID, SEGMENT_NUMBER),
    	CONSTRAINT FLTS_FK
    	FOREIGN KEY (FLIGHT_ID, SEGMENT_NUMBER)
    	REFERENCES Flights (FLIGHT_ID, SEGMENT_NUMBER)
    	);
    -- add a unique constraint to a column
    ALTER TABLE SAMP.PROJECT
    ADD CONSTRAINT P_UC UNIQUE (PROJNAME);

    -- create a table whose city_id column references the
    -- primary key in the Cities table
    -- using a column-level foreign key constraint
    CREATE TABLE CONDOS
    	(
    	CONDO_ID INT NOT NULL CONSTRAINT hotels_PK PRIMARY KEY,
    	CONDO_NAME VARCHAR(40) NOT NULL,
    	CITY_ID INT CONSTRAINT city_foreign_key
    	REFERENCES Cities ON DELETE CASCADE ON UPDATE RESTRICT
    	);

Statement dependency system
INSERT and UPDATE statements depend on all constraints on the target table. DELETEs depend on unique, primary key, and foreign key constraints. These statements are invalidated if a constraint is added to or dropped from the target table.
Column-level-constraint

    {
        NOT NULL |
        [ [CONSTRAINT constraint-Name]
        {
            CHECK (searchCondition) |
            {
                PRIMARY KEY |
                UNIQUE |
                REFERENCES clause
            }
        }
    }

Table-level constraint

    [CONSTRAINT constraint-Name]
    {
        CHECK (searchCondition) |
        {
            PRIMARY KEY ( Simple-column-Name [ , Simple-column-Name ]* ) |
            UNIQUE ( Simple-column-Name [ , Simple-column-Name ]* ) |
            FOREIGN KEY ( Simple-column-Name [ , Simple-column-Name ]* )
    REFERENCES clause
        }
    }

References specification

    REFERENCES table-Name [ ( Simple-column-Name [ , Simple-column-Name ]* ) ]
    [ ON DELETE {NO ACTION | RESTRICT | CASCADE | SET NULL}]
       [ ON UPDATE {NO ACTION | RESTRICT }]
    |
    [ ON UPDATE {NO ACTION | RESTRICT }] [ ON DELETE
       {NO ACTION | RESTRICT | CASCADE | SET NULL}]

searchCondition
A searchCondition is any Boolean expression that meets the requirements specified in Requirements for search condition.
If a constraint-Name is not specified, Derby generates a unique constraint name (for either column or table constraints).
FOR UPDATE clause
The FOR UPDATE clause is an optional part of a SELECT statement. Cursors are read-only by default. The FOR UPDATE clause specifies that the cursor should be updatable, and enforces a check during compilation that the SELECT statement meets the requirements for an updatable cursor. For more information about updatability, see Requirements for Updatable Cursors.
Syntax

    FOR
    {
        READ ONLY | FETCH ONLY |
        UPDATE [ OF Simple-column-Name [ , Simple-column-Name]* ]
    }

Simple-column-Name refers to the names visible for the table specified in the FROM clause of the underlying query.
Note: The use of the FOR UPDATE clause is not mandatory to obtain an updatable JDBC ResultSet. As long as the statement used to generate the JDBC ResultSet meets the requirements for updatable cursor, it is sufficient for the JDBC Statement that generates the JDBC ResultSet to have concurrency mode ResultSet.CONCUR_UPDATABLE for the ResultSet to be updatable.
The optimizer is able to use an index even if the column in the index is being updated. For more information about how indexes affect cursors, see Tuning Java DB.

    SELECT RECEIVED, SOURCE, SUBJECT, NOTE_TEXT FROM SAMP.IN_TRAY FOR UPDATE

FROM clause
The FROM clause is a mandatory clause in a SelectExpression. It specifies the tables (TableExpression) from which the other clauses of the query can access columns for use in expressions.
Syntax

    FROM TableExpression [ , TableExpression ] *

    SELECT Cities.city_id
    FROM Cities
    WHERE city_id < 5
    -- other types of TableExpressions
    SELECT TABLENAME, ISINDEX
    FROM SYS.SYSTABLES T, SYS.SYSCONGLOMERATES C
    WHERE T.TABLEID = C.TABLEID
    ORDER BY TABLENAME, ISINDEX
    -- force the join order
    SELECT *
    FROM Flights, FlightAvailability
    WHERE FlightAvailability.flight_id = Flights.flight_id
    AND FlightAvailability.segment_number = Flights.segment_number
    AND Flights.flight_id < 'AA1115'
    -- a TableExpression can be a joinOperation. Therefore
    -- you can have multiple join operations in a FROM clause
    SELECT COUNTRIES.COUNTRY, CITIES.CITY_NAME, FLIGHTS.DEST_AIRPORT
    FROM COUNTRIES LEFT OUTER JOIN CITIES
    ON COUNTRIES.COUNTRY_ISO_CODE = CITIES.COUNTRY_ISO_CODE
    LEFT OUTER JOIN FLIGHTS
    ON Cities.AIRPORT = FLIGHTS.DEST_AIRPORT

GROUP BY clause
A GROUP BY clause, part of a SelectExpression, groups a result into subsets that have matching values for one or more columns. In each group, no two rows have the same value for the grouping column or columns. NULLs are considered equivalent for grouping purposes.
You typically use a GROUP BY clause in conjunction with an aggregate expression.
Syntax

    GROUP BY column-Name [ , column-Name ] *

column-Name must be a column from the current scope of the query; there can be no columns from a query block outside the current scope. For example, if a GROUP BY clause is in a subquery, it cannot refer to columns in the outer query.
SelectItems in the SelectExpression with a GROUP BY clause must contain only aggregates or grouping columns.

    -- find the average flying_times of flights grouped by
    -- airport
    SELECT AVG (flying_time), orig_airport
    FROM Flights
    GROUP BY orig_airport

    SELECT MAX(city_name), region
    FROM Cities, Countries
    WHERE Cities.country_ISO_code = Countries.country_ISO_code
    GROUP BY region
    -- group by an a smallint
    SELECT ID, AVG(SALARY)
    FROM SAMP.STAFF
    GROUP BY ID
    -- Get the AVGSALARY and EMPCOUNT columns, and the DEPTNO column using the AS clause
    -- And group by the WORKDEPT column using the correlation name OTHERS
    SELECT OTHERS.WORKDEPT AS DEPTNO,
    AVG(OTHERS.SALARY) AS AVGSALARY,
    COUNT(*) AS EMPCOUNT
    FROM SAMP.EMPLOYEE OTHERS
    GROUP BY OTHERS.WORKDEPT

HAVING clause
A HAVING clause restricts the results of a GROUP BY in a SelectExpression. The HAVING clause is applied to each group of the grouped table, much as a WHERE clause is applied to a select list. If there is no GROUP BY clause, the HAVING clause is applied to the entire result as a single group. The SELECT clause cannot refer directly to any column that does not have a GROUP BY clause. It can, however, refer to constants, aggregates, and special registers.
Syntax

    HAVING searchCondition

The searchCondition, which is a specialized booleanExpression, can contain only grouping columns (see GROUP BY clause), columns that are part of aggregate expressions, and columns that are part of a subquery. For example, the following query is illegal, because the column SALARY is not a grouping column, it does not appear within an aggregate, and it is not within a subquery:

    -- SELECT COUNT(*)
    -- FROM SAMP.STAFF
    -- GROUP BY ID
    -- HAVING SALARY > 15000

Aggregates in the HAVING clause do not need to appear in the SELECT list. If the HAVING clause contains a subquery, the subquery can refer to the outer query block if and only if it refers to a grouping column.

    -- Find the total number of economy seats taken on a flight,
    -- grouped by airline,
    -- only when the group has at least 2 records.
    SELECT SUM(ECONOMY_SEATS_TAKEN), AIRLINE_FULL
    FROM FLIGHTAVAILABILITY, AIRLINES
    WHERE SUBSTR(FLIGHTAVAILABILITY.FLIGHT_ID, 1, 2) = AIRLINE
    GROUP BY AIRLINE_FULL
    HAVING COUNT(*) > 1

ORDER BY clause
The ORDER BY clause is an optional element of a SELECT statement. An ORDER BY clause allows you to specify the order in which rows appear in the ResultSet.
Syntax

    ORDER BY { column-Name | ColumnPosition | Expression }
        [ ASC | DESC ]
        [ , column-Name | ColumnPosition | Expression
            [ ASC | DESC ] ] *

column-Name
Refers to the names visible from the SelectItems in the underlying query of the SELECT statement. The column-Name that you specify in the ORDER BY clause does not need to be the SELECT list.
ColumnPosition
An integer that identifies the number of the column in the SelectItems in the underlying query of the SELECT statement. ColumnPosition must be greater than 0 and not greater than the number of columns in the result table. In other words, if you want to order by a column, that column must be specified in the SELECT list.
Expression
A sort key expression, such as numeric, string, and datetime expressions. Expression can also be a row value expression such as a scalar subquery or case expression.
ASC
Specifies that the results should be returned in ascending order. If the order is not specified, ASC is the default.
DESC
Specifies that the results should be returned in descending order.
Notes

• |  | If SELECT DISTINCT is specified or if the SELECT statement contains a GROUP BY clause, the ORDER BY columns must be in the SELECT list.
• |  | An ORDER BY clause prevents a SELECT statement from being an updatable cursor. For more information, see Requirements for updatable cursors and updatable ResultSets. For example, if an INTEGER column contains integers, NULL is considered greater than 1 for purposes of sorting. In other words, NULL values are sorted high.

Example using a correlation name
You can sort the result set by a correlation name, if the correlation name is specified in the select list. For example, to return from the CITIES database all of the entries in the CITY_NAME and COUNTRY columns, where the COUNTRY column has the correlation name NATION, you specify this SELECT statement:

    SELECT CITY_NAME, COUNTRY AS NATION
        FROM CITIES
        ORDER BY NATION

Example using a numeric expression
You can sort the result set by a numeric expression, for example:

    SELECT name, salary, bonus FROM employee
       ORDER BY salary+bonus

In this example, the salary and bonus columns are DECIMAL data types.
Example using a function
You can sort the result set by invoking a function, for example:

    SELECT i, len FROM measures
       ORDER BY sin(i)

WHERE clause
A WHERE clause is an optional part of a SelectExpression, DELETE statement, or UPDATE statement. The WHERE clause lets you select rows based on a boolean expression. Only rows for which the expression evaluates to TRUE are returned in the result, or, in the case of a DELETE statement, deleted, or, in the case of an UPDATE statement, updated.
Syntax

    WHERE Boolean expression

Boolean expressions are allowed in the WHERE clause. Most of the general expressions listed in Table of general expressions, can result in a boolean value.
In addition, there are the more common boolean expressions. Specific boolean operators listed in Table 10, take one or more operands; the expressions return a boolean value.
Example

    -- find the flights where no business-class seats have
    -- been booked
    SELECT *
    FROM FlightAvailability
    WHERE business_seats_taken IS NULL
    OR business_seats_taken = 0
    -- Join the EMP_ACT and EMPLOYEE tables
    -- select all the columns from the EMP_ACT table and
    -- add the employee's surname (LASTNAME) from the EMPLOYEE table
    -- to each row of the result.
    SELECT SAMP.EMP_ACT.*, LASTNAME
      FROM SAMP.EMP_ACT, SAMP.EMPLOYEE
      WHERE EMP_ACT.EMPNO = EMPLOYEE.EMPNO
    -- Determine the employee number and salary of sales representatives
    -- along with the average salary and head count of their departments.
    -- This query must first create a new-column-name specified in the AS clause
    -- which is outside the fullselect (DINFO)
    -- in order to get the AVGSALARY and EMPCOUNT columns,
    -- as well as the DEPTNO column that is used in the WHERE clause
    SELECT THIS_EMP.EMPNO, THIS_EMP.SALARY, DINFO.AVGSALARY, DINFO.EMPCOUNT
     FROM EMPLOYEE THIS_EMP,
       (SELECT OTHERS.WORKDEPT AS DEPTNO,
               AVG(OTHERS.SALARY) AS AVGSALARY,
               COUNT(*) AS EMPCOUNT
        FROM EMPLOYEE OTHERS
        GROUP BY OTHERS.WORKDEPT
       )AS DINFO
     WHERE THIS_EMP.JOB = 'SALESREP'
    	   AND THIS_EMP.WORKDEPT = DINFO.DEPTNO

WHERE CURRENT OF clause
The WHERE CURRENT OF clause is a clause in some UPDATE and DELETE statements. It allows you to perform positioned updates and deletes on updatable cursors. For more information about updatable cursors, see SELECT statement.
Syntax

    WHERE CURRENT OF cursor-Name

    Statement s = conn.createStatement();
    s.setCursorName("AirlinesResults");
    ResultSet rs = conn.executeQuery(
        "SELECT Airline, basic_rate " +
        "FROM Airlines FOR UPDATE OF basic_rate");
    Statement s2 = conn.createStatement();
    s2.executeUpdate("UPDATE Airlines SET basic_rate = basic_rate " +
        "+ .25 WHERE CURRENT OF AirlinesResults");

SQL expressions
Syntax for many statements and expressions includes the term Expression, or a term for a specific kind of expression such as TableSubquery. Expressions are allowed in these specified places within statements.
Some locations allow only a specific type of expression or one with a specific property. If not otherwise specified, an expression is permitted anywhere the word Expression appears in the syntax. This includes:

• |  | ORDER BY clause
• |  | SelectExpression
• |  | UPDATE statement (SET portion)
• |  | VALUES Expression
• |  | WHERE clause

Of course, many other statements include these elements as building blocks, and so allow expressions as part of these elements.
The following tables list all the possible SQL expressions and indicate where the expressions are allowed.
General expressions
General expressions are expressions that might result in a value of any type.
Table 2. Table of general expressions

Expression Type | Explanation
Column reference | A column-Name that references the value of the column made visible to the expression containing the Column reference. You must qualify the column-Name by the table name or correlation name if it is ambiguous. The qualifier of a column-Name must be the correlation name, if a correlation name is given to a table that is in a FROM clause. The table name is no longer visible as a column-Name qualifier once it has been aliased by a correlation name. Allowed in SelectExpressions, UPDATE statements, and the WHERE clauses of data manipulation statements.
Constant | Most built-in data types typically have constants associated with them (as shown in Data types).
NULL | NULL is an untyped constant representing the unknown value. Allowed in CAST expressions or in INSERT VALUES lists and UPDATE SET clauses. Using it in a CAST expression gives it a specific data type.
Dynamic parameter | A dynamic parameter is a parameter to an SQL statement for which the value is not specified when the statement is created. Instead, the statement has a question mark (?) as a placeholder for each dynamic parameter. See Dynamic parameters. Dynamic parameters are permitted only in prepared statements. You must specify values for them before the prepared statement is executed. The values specified must match the types expected. Allowed anywhere in an expression where the data type can be easily deduced. See Dynamic parameters.
CAST expression | Lets you specify the type of NULL or of a dynamic parameter or convert a value to another type. See CAST function.
Scalar subquery | Subquery that returns a single row with a single column. See ScalarSubquery.
Table subquery | Subquery that returns more than one column and more than one row. See TableSubquery. Allowed as a tableExpression in a FROM clause and with EXISTS, IN, and quantified comparisons.
Conditional expression | A conditional expression chooses an expression to evaluate based on a boolean test.

Boolean expressions
Boolean expressions are expressions that result in boolean values. Most general expressions can result in boolean values. Boolean expressions commonly used in a WHERE clause are made of operands operated on by SQL operators. See SQL Boolean Operators.
Numeric expressions
Numeric expressions are expressions that result in numeric values. Most of the general expressions can result in numeric values. Numeric values have one of the following types:

• |  | BIGINT
• |  | DECIMAL
• |  | DOUBLE PRECISION
• |  | INTEGER
• |  | REAL
• |  | SMALLINT

Table 3. Table of numeric expressions

Expression Type | Explanation
+, -, *, /, unary + and - expressions | Evaluate the expected math operation on the operands. If both operands are the same type, the result type is not promoted, so the division operator on integers results in an integer that is the truncation of the actual numeric result. When types are mixed, they are promoted as described in Data types. Unary + is a noop (i.e., +4 is the same as 4). Unary - is the same as multiplying the value by -1, effectively changing its sign.
AVG | Returns the average of a set of numeric values. AVG function
SUM | Returns the sum of a set of numeric values. SUM function
LENGTH | Returns the number of characters in a character or bit string. See LENGTH function.
LOWER | See LCASE or LOWER function.
COUNT | Returns the count of a set of values. See COUNT function, COUNT(*) function.

Character expressions
Character expressions are expressions that result in a CHAR or VARCHAR value. Most general expressions can result in a CHAR or VARCHAR value.
Table 4. Table of character expressions

Expression Type | Explanation
A CHAR or VARCHAR value that uses wildcards. | The wildcards % and _ make a character string a pattern against which the LIKE operator can look for a match.
Concatenation expression | In a concatenation expression, the concatenation operator, "||", concatenates its right operand to the end of its left operand. Operates on character and bit strings. See Concatenation operator.
Built-in string functions | The built-in string functions act on a String and return a string. See LTRIM function, LCASE or LOWER function, RTRIM function, TRIM function, SUBSTR function, and UCASE or UPPER function.
USER functions | User functions return information about the current user as a String. See CURRENT_USER function, SESSION_USER function, and .

Date and time expressions
A date or time expression results in a DATE, TIME, or TIMESTAMP value. Most of the general expressions can result in a date or time value.
Table 5. Table of date and time expressions

Expression type | Explanation
CURRENT_DATE | Returns the current date. See CURRENT_DATE function.
CURRENT_TIME | Returns the current time. See CURRENT_TIME function.
CURRENT_TIMESTAMP | Returns the current timestamp. See CURRENT_TIMESTAMP function.

SelectExpression
A SelectExpression is the basic SELECT-FROM-WHERE construct used to build a table value based on filtering and projecting values from other tables.
Syntax

    SELECT [ DISTINCT | ALL ] SelectItem [ , SelectItem ]*
    FROM clause
    [ WHERE clause]
    [ GROUP BY clause ]
    [ HAVING clause ]

SelectItem:

    {
        * |
        { table-Name | correlation-Name } .* |
        Expression [AS Simple-column-Name]
    }

The SELECT clause contains a list of expressions and an optional quantifier that is applied to the results of the FROM clause and the WHERE clause. If DISTINCT is specified, only one copy of any row value is included in the result. Nulls are considered duplicates of one another for the purposes of DISTINCT. If no quantifier, or ALL, is specified, no rows are removed from the result in applying the SELECT clause (ALL is the default).
A SelectItem projects one or more result column values for a table result being constructed in a SelectExpression.
The result of the FROM clause is the cross product of the FROM items. The WHERE clause can further qualify this result.
The WHERE clause causes rows to be filtered from the result based on a boolean expression. Only rows for which the expression evaluates to TRUE are returned in the result.
The GROUP BY clause groups rows in the result into subsets that have matching values for one or more columns. GROUP BY clauses are typically used with aggregates.
If there is a GROUP BY clause, the SELECT clause must contain only aggregates or grouping columns. If you want to include a non-grouped column in the SELECT clause, include the column in an aggregate expression. For example:

    -- List head count of each department,
    -- the department number (WORKDEPT), and the average departmental salary (SALARY)
    -- for all departments in the EMPLOYEE table.
    -- Arrange the result table in ascending order by average departmental salary.
    SELECT WORKDEPT, AVG(SALARY)
         FROM EMPLOYEE
         GROUP BY WORKDEPT
         ORDER BY 1

If there is no GROUP BY clause, but a SelectItem contains an aggregate not in a subquery, the query is implicitly grouped. The entire table is the single group.
The HAVING clause restricts a grouped table, specifying a search condition (much like a WHERE clause) that can refer only to grouping columns or aggregates from the current scope. The HAVING clause is applied to each group of the grouped table. If the HAVING clause evaluates to TRUE, the row is retained for further processing. If the HAVING clause evaluates to FALSE or NULL, the row is discarded. If there is a HAVING clause but no GROUP BY, the table is implicitly grouped into one group for the entire table.
Derby processes a SelectExpression in the following order:

• |  | FROM clause
• |  | WHERE clause
• |  | GROUP BY (or implicit GROUP BY)
• |  | HAVING clause
• |  | SELECT clause

The result of a SelectExpression is always a table.
When a query does not have a FROM clause (when you are constructing a value, not getting data out of a table), you use a VALUES statement, not a SelectExpression. For example:

    VALUES CURRENT_TIMESTAMP

See VALUES Expression.
The * wildcard
* expands to all columns in the tables in the associated FROM clause.
table-Name.* and correlation-Name.* expand to all columns in the identified table. That table must be listed in the associated FROM clause.
Naming columns
You can name a SelectItem column using the AS clause. If a column of a SelectItem is not a simple ColumnReference expression or named with an AS clause, it is given a generated unique name.
These column names are useful in several cases:

• |  | They are made available on the JDBC ResultSetMetaData.
• |  | They are used as the names of the columns in the resulting table when the SelectExpression is used as a table subquery in a FROM clause.
• |  | They are used in the ORDER BY clause as the column names available for sorting.

    -- this example shows SELECT-FROM-WHERE
    -- with an ORDER BY clause
    -- and correlation-Names for the tables
    SELECT CONSTRAINTNAME, COLUMNNAME
    FROM SYS.SYSTABLES t, SYS.SYSCOLUMNS col,
    SYS.SYSCONSTRAINTS cons, SYS.SYSCHECKS checks
    WHERE t.TABLENAME = 'FLIGHTS' AND t.TABLEID = col.
    REFERENCEID AND t.TABLEID = cons.TABLEID
    AND cons.CONSTRAINTID = checks.CONSTRAINTID
    ORDER BY CONSTRAINTNAME
    -- This example shows the use of the DISTINCT clause
    SELECT DISTINCT ACTNO
    FROM EMP_ACT
    -- This example shows how to rename an expression
    -- Using the EMPLOYEE table, list the department number (WORKDEPT) and
    -- maximum departmental salary (SALARY) renamed as BOSS
    -- for all departments whose maximum salary is less than the
    -- average salary in all other departments.
    SELECT WORKDEPT AS DPT, MAX(SALARY) AS BOSS
    	FROM EMPLOYEE EMP_COR
    	GROUP BY WORKDEPT
    	HAVING MAX(SALARY) < (SELECT AVG(SALARY)
    				FROM EMPLOYEE
    				WHERE NOT WORKDEPT = EMP_COR.WORKDEPT)
    	ORDER BY BOSS

TableExpression
A TableExpression specifies a table or view in a FROM clause. It is the source from which a SelectExpression selects a result.
A correlation name can be applied to a table in a TableExpression so that its columns can be qualified with that name. If you do not supply a correlation name, the table name qualifies the column name. When you give a table a correlation name, you cannot use the table name to qualify columns. You must use the correlation name when qualifying column names.
No two items in the FROM clause can have the same correlation name, and no correlation name can be the same as an unqualified table name specified in that FROM clause.
In addition, you can give the columns of the table new names in the AS clause. Some situations in which this is useful:

• |  | When a VALUES expression is used as a TableSubquery, since there is no other way to name the columns of a VALUES expression.
• |  | When column names would otherwise be the same as those of columns in other tables; renaming them means you don't have to qualify them.

The Query in a TableSubquery appearing in a FromItem can contain multiple columns and return multiple rows. See TableSubquery.
For information about the optimizer overrides you can specify, see Tuning Java DB.
Syntax

    {
    TableOrViewExpression | JOIN operation
    }

Example

    -- SELECT from a Join expression
    SELECT E.EMPNO, E.LASTNAME, M.EMPNO, M.LASTNAME
     FROM EMPLOYEE E LEFT OUTER JOIN
       	DEPARTMENT INNER JOIN EMPLOYEE M
      ON MGRNO = M.EMPNO
      ON E.WORKDEPT = DEPTNO

TableOrViewExpression

    {table-Name |view-Name}
        [ [ AS ] correlation-Name
            [ (Simple-column-Name [ , Simple-column-Name]* ) ] ] ]

VALUES expression
The VALUES expression allows construction of a row or a table from other values. A VALUES expression can be used in all the places where a query can, and thus can be used in any of the following ways:

• |  | As a statement that returns a ResultSet
• |  | Within expressions and statements wherever subqueries are permitted
• |  | As the source of values for an INSERT statement (in an INSERT statement, you normally use a VALUES expression when you do not use a SelectExpression)

Syntax

    {
        VALUES ( Value {, Value }* )
            [ , ( Value {, Value }* ) ]* |
        VALUES Value [ , Value ]*
     }

where Value is defined as

    Expression | DEFAULT

The first form constructs multi-column rows. The second form constructs single-column rows, each expression being the value of the column of the row.
The DEFAULT keyword is allowed only if the VALUES expression is in an INSERT statement. Specifying DEFAULT for a column inserts the column's default value into the column. Another way to insert the default value into the column is to omit the column from the column list and only insert values into other columns in the table.
Examples

    -- 3 rows of 1 column
    VALUES (1),(2),(3)
    -- 3 rows of 1 column
    VALUES 1, 2, 3
    -- 1 row of 3 columns
    VALUES (1, 2, 3)
    -- 3 rows of 2 columns
    VALUES (1,21),(2,22),(3,23)
    -- constructing a derived table
    VALUES ('orange', 'orange'), ('apple', 'red'),
    ('banana', 'yellow')
    -- Insert two new departments using one statement into the DEPARTMENT table,
    -- but do not assign a manager to the new department.
    INSERT INTO DEPARTMENT (DEPTNO, DEPTNAME, ADMRDEPT)
      VALUES ('B11', 'PURCHASING', 'B01'),
        ('E41', 'DATABASE ADMINISTRATION', 'E01')
    -- insert a row with a DEFAULT value for the MAJPROJ column
    INSERT INTO PROJECT (PROJNO, PROJNAME, DEPTNO, RESPEMP, PRSTDATE, MAJPROJ)
    VALUES ('PL2101', 'ENSURE COMPAT PLAN', 'B01', '000020', CURRENT_DATE, DEFAULT)

    -- using a built-in function
    VALUES CURRENT_DATE
    -- getting the value of an arbitrary expression
    VALUES (3*29, 26.0E0/3)
    -- getting a value returned by a built-in function
    values char(1)

Expression precedence
Precedence of operations from highest to lowest is:

• |  | (), ?, Constant (including sign), NULL, ColumnReference, ScalarSubquery, CAST
• |  | LENGTH, CURRENT_DATE, CURRENT_TIME, CURRENT_TIMESTAMP, and other built-ins
• |  | unary + and -
• |  | *, /, || (concatenation)
• |  | binary + and -
• |  | comparisons, quantified comparisons, EXISTS, IN, IS NULL, LIKE, BETWEEN, IS
• |  | NOT
• |  | AND
• |  | OR

You can explicitly specify precedence by placing expressions within parentheses. An expression within parentheses is evaluated before any operations outside the parentheses are applied to it.
Example

    (3+4)*9
    (age < 16 OR age > 65) AND employed = TRUE

Boolean expressions
Boolean expressions are allowed in WHERE clauses and in check constraints. Boolean expressions in check constraints have limitations not noted here; see CONSTRAINT clause for more information. Boolean expressions in a WHERE clause have a highly liberal syntax; see WHERE clause, for example.
A boolean expression can include a boolean operator or operators. These are listed in SQL Boolean Operators.
Table 6. SQL Boolean Operators

Operator | Explanation and Example | Syntax
AND, OR, NOT | Evaluate any operand(s) that are boolean expressions
    (orig_airport = 'SFO') OR
        (dest_airport = 'GRU')
        -- returns true
    {
      Expression AND
        Expression |
      Expression OR
        Expression |
      NOT Expression
    }
Comparisons | <, =, >, <=, >=, <> are applicable to all of the built-in types.
    DATE('1998-02-26') <
        DATE('1998-03-01')
    -- returns true
    Expression
    {
      < |
      = |
      > |
      <= |
      >= |
      <>
    }
    Expression
IS NULL, IS NOT NULL | Test whether the result of an expression is null or not.
    WHERE MiddleName IS NULL
    Expression IS [ NOT ]
      NULL
LIKE | Attempts to match a character expression to a character pattern, which is a character string that includes one or more wildcards. % matches any number (zero or more) of characters in the corresponding position in first character expression. _ matches one character in the corresponding position in the character expression. Any other character matches only that character in the corresponding position in the character expression.
    city LIKE 'Sant_'
To treat % or _ as constant characters, escape the character with an optional escape character, which you specify with the ESCAPE clause.
    SELECT a FROM tabA WHERE a
    LIKE '%=_' ESCAPE '='
    CharacterExpression
      [ NOT ] LIKE
      CharacterExpression
      WithWildCard
      [ ESCAPE

    'escapeCharacter']
BETWEEN | Tests whether the first operand is between the second and third operands. The second operand must be less than the third operand. Applicable only to types to which <= and >= can be applied.
    WHERE booking_date BETWEEN
        DATE('1998-02-26') AND
        DATE('1998-03-01')
    Expression [ NOT ]
    BETWEEN Expression
      AND Expression
IN | Operates on table subquery or list of values. Returns TRUE if the left expression's value is in the result of the table subquery or in the list of values. Table subquery can return multiple rows but must return a single column.
    WHERE booking_date NOT IN
        (SELECT booking_date FROM
    HotelBookings WHERE rooms_available = 0)
    {
      Expression [ NOT ]
        IN
        TableSubquery |
      Expression [ NOT ]
        IN ( Expression
        [, Expression ]* )
    }
EXISTS | Operates on a table subquery. Returns TRUE if the table subquery returns any rows, and FALSE if it returns no rows. Table subquery can return multiple columns (only if you use * to denote multiple columns) and rows.
    WHERE EXISTS
      (SELECT *
      FROM Flights
      WHERE dest_airport = 'SFO'
      AND orig_airport = 'GRU')
    [NOT] EXISTS TableSubquery
Quantified comparison | A quantified comparison is a comparison operator (<, =, >, <=, >=, <>) with ALL or ANY or SOME applied. Operates on table subqueries, which can return multiple rows but must return a single column. If ALL is used, the comparison must be true for all values returned by the table subquery. If ANY or SOME is used, the comparison must be true for at least one value of the table subquery. ANY and SOME are equivalent.
    WHERE normal_rate < ALL
    (SELECT budget/550 FROM Groups)
    Expression
      ComparisonOperator
      {
        ALL |
        ANY |
        SOME
      }
      TableSubquery

Dynamic parameters
You can prepare statements that are allowed to have parameters for which the value is not specified when the statement is prepared using PreparedStatement methods in the JDBC API. These parameters are called dynamic parameters and are represented by a ?.
The JDBC API documents refer to dynamic parameters as IN, INOUT, or OUT parameters. In SQL, they are always IN parameters.
New: Derby supports the interface ParameterMetaData, new in JDBC 3.0. This interface describes the number, type, and properties of prepared statement parameters. See the Java DB Developer's Guide for more information.
You must specify values for them before executing the statement. The values specified must match the types expected.
Dynamic parameters example

    PreparedStatement ps2 = conn.prepareStatement(
        "UPDATE HotelAvailability SET rooms_available = " +
        "(rooms_available - ?) WHERE hotel_id = ? " +
        "AND booking_date BETWEEN ? AND ?");
    -- this sample code sets the values of dynamic parameters
    -- to be the values of program variables
    ps2.setInt(1, numberRooms);
    ps2.setInt(2, theHotel.hotelId);
    ps2.setDate(3, arrival);
    ps2.setDate(4, departure);
    updateCount = ps2.executeUpdate();

Where dynamic parameters are allowed
You can use dynamic parameters anywhere in an expression where their data type can be easily deduced.

1. |  | Use as the first operand of BETWEEN is allowed if one of the second and third operands is not also a dynamic parameter. The type of the first operand is assumed to be the type of the non-dynamic parameter, or the union result of their types if both are not dynamic parameters.
    WHERE ? BETWEEN DATE('1996-01-01') AND ?
    -- types assumed to be DATES
2. |  | Use as the second or third operand of BETWEEN is allowed. Type is assumed to be the type of the left operand.
    WHERE DATE('1996-01-01') BETWEEN ? AND ?
    -- types assumed to be DATES
3. |  | Use as the left operand of an IN list is allowed if at least one item in the list is not itself a dynamic parameter. Type for the left operand is assumed to be the union result of the types of the non-dynamic parameters in the list.
    WHERE ? NOT IN (?, ?, 'Santiago')
    -- types assumed to be CHAR
4. |  | Use in the values list in an IN predicate is allowed if the first operand is not a dynamic parameter or its type was determined in the previous rule. Type of the dynamic parameters appearing in the values list is assumed to be the type of the left operand.
    WHERE FloatColumn IN (?, ?, ?)
    -- types assumed to be FLOAT
5. |  | For the binary operators +, -, *, /, AND, OR, <, >, =, <>, <=, and >=, use of a dynamic parameter as one operand but not both is permitted. Its type is taken from the other side.
    WHERE ? < CURRENT_TIMESTAMP
    -- type assumed to be a TIMESTAMP
6. |  | Use in a CAST is always permitted. This gives the dynamic parameter a type.
    CALL valueOf(CAST (? AS VARCHAR(10)))
7. |  | Use on either or both sides of LIKE operator is permitted. When used on the left, the type of the dynamic parameter is set to the type of the right operand, but with the maximum allowed length for the type. When used on the right, the type is assumed to be of the same length and type as the left operand. (LIKE is permitted on CHAR and VARCHAR types; see Concatenation operator for more information.)
    WHERE ? LIKE 'Santi%'
    -- type assumed to be CHAR with a length of
    -- java.lang.Integer.MAX_VALUE
8. |  | A ? parameter is allowed by itself on only one side of the || operator. That is, "? || ?" is not allowed. The type of a ? parameter on one side of a || operator is determined by the type of the expression on the other side of the || operator. If the expression on the other side is a CHAR or VARCHAR, the type of the parameter is VARCHAR with the maximum allowed length for the type. If the expression on the other side is a CHAR FOR BIT DATA or VARCHAR FOR BIT DATA type, the type of the parameter is VARCHAR FOR BIT DATA with the maximum allowed length for the type.
    SELECT BITcolumn || ?
    FROM UserTable
    -- Type assumed to be CHAR FOR BIT DATA of length specified for BITcolumn
9. |  | In a conditional expression, which uses a ?, use of a dynamic parameter (which is also represented as a ?) is allowed. The type of a dynamic parameter as the first operand is assumed to be boolean. Only one of the second and third operands can be a dynamic parameter, and its type will be assumed to be the same as that of the other (that is, the third and second operand, respectively).
    SELECT c1 IS NULL ? ? : c1
    -- allows you to specify a "default" value at execution time
    -- dynamic parameter assumed to be the type of c1
    -- you cannot have dynamic parameters on both sides
    -- of the :
10. |  | A dynamic parameter is allowed as an item in the values list or select list of an INSERT statement. The type of the dynamic parameter is assumed to be the type of the target column.
    INSERT INTO t VALUES (?)
    -- dynamic parameter assumed to be the type
    -- of the only column in table t
    INSERT INTO t SELECT ?
    FROM t2
    -- not allowed
11. |  | A ? parameter in a comparison with a subquery takes its type from the expression being selected by the subquery. For example:
    SELECT *
    FROM tab1
    WHERE ? = (SELECT x FROM tab2)

    SELECT *
    FROM tab1
    WHERE ? = ANY (SELECT x FROM tab2)
    -- In both cases, the type of the dynamic parameter is
    -- assumed to be the same as the type of tab2.x.
12. |  | A dynamic parameter is allowed as the value in an UPDATE statement. The type of the dynamic parameter is assumed to be the type of the column in the target table.
    UPDATE t2 SET c2 =? -- type is assumed to be type of c2
13. |  | Dynamic parameters are allowed as the operand of the unary operators - or +. For example:
    CREATE TABLE t1 (c11 INT, c12 SMALLINT, c13 DOUBLE, c14 CHAR(3))
    SELECT * FROM t1 WHERE c11 BETWEEN -? AND +?
    -– The type of both of the unary operators is INT
    -- based on the context in which they are used (that is,
    -- because c11 is INT, the unary parameters also get the
    -- type INT.
14. |  | LENGTH allow a dynamic parameter. The type is assumed to be a maximum length VARCHAR type.
    SELECT LENGTH(?)
15. |  | Qualified comparisons.
    ? = SOME (SELECT 1 FROM t)
    -- is valid. Dynamic parameter assumed to be INTEGER type
    1 = SOME (SELECT ? FROM t)
    -- is valid. Dynamic parameter assumed to be INTEGER type.
16. |  | A dynamic parameter is allowed as the left operand of an IS expression and is assumed to be a boolean.

Once the type of a dynamic parameter is determined based on the expression it is in, that expression is allowed anywhere it would normally be allowed if it did not include a dynamic parameter.
JOIN operations
The JOIN operations, which are among the possible TableExpressions in a FROM clause, perform joins between two tables. (You can also perform a join between two tables using an explicit equality test in a WHERE clause, such as "WHERE t1.col1 = t2.col2".)
Syntax

    JOIN Operation

The JOIN operations are:

• |  | INNER JOIN operation Specifies a join between two tables with an explicit join clause. See INNER JOIN operation.
• |  | LEFT OUTER JOIN operation Specifies a join between two tables with an explicit join clause, preserving unmatched rows from the first table. See LEFT OUTER JOIN operation.
• |  | RIGHT OUTER JOIN operation Specifies a join between two tables with an explicit join clause, preserving unmatched rows from the second table. See RIGHT OUTER JOIN operation.

In all cases, you can specify additional restrictions on one or both of the tables being joined in outer join clauses or in the WHERE clause.
JOIN expressions and query optimization
For information on which types of joins are optimized, see Tuning Java DB.
INNER JOIN operation
An INNER JOIN is a JOIN operation that allows you to specify an explicit join clause.
Syntax

    TableExpression [ INNER ] JOIN TableExpression { ON booleanExpression }

You can specify the join clause by specifying ON with a boolean expression.
The scope of expressions in the ON clause includes the current tables and any tables in outer query blocks to the current SELECT. In the following example, the ON clause refers to the current tables:

    SELECT *
    FROM SAMP.EMPLOYEE INNER JOIN SAMP.STAFF
    ON EMPLOYEE.SALARY < STAFF.SALARY

The ON clause can reference tables not being joined and does not have to reference either of the tables being joined (though typically it does).

    -- Join the EMP_ACT and EMPLOYEE tables
    -- select all the columns from the EMP_ACT table and
    -- add the employee's surname (LASTNAME) from the EMPLOYEE table
    -- to each row of the result
    SELECT SAMP.EMP_ACT.*, LASTNAME
         FROM SAMP.EMP_ACT JOIN SAMP.EMPLOYEE
         ON EMP_ACT.EMPNO = EMPLOYEE.EMPNO
    -- Join the EMPLOYEE and DEPARTMENT tables,
    -- select the employee number (EMPNO),
    -- employee surname (LASTNAME),
    -- department number (WORKDEPT in the EMPLOYEE table and DEPTNO in the
    -- DEPARTMENT table)
    -- and department name (DEPTNAME)
    -- of all employees who were born (BIRTHDATE) earlier than 1930.
    SELECT EMPNO, LASTNAME, WORKDEPT, DEPTNAME
         FROM SAMP.EMPLOYEE JOIN SAMP.DEPARTMENT
         ON WORKDEPT = DEPTNO
         AND YEAR(BIRTHDATE) < 1930

    -- Another example of "generating" new data values,
    -- using a query which selects from a VALUES clause (which is an
    -- alternate form of a fullselect).
    -- This query shows how a table can be derived called "X"
    -- having 2 columns "R1" and "R2" and 1 row of data
    SELECT *
    FROM (VALUES (3, 4), (1, 5), (2, 6))
    AS VALUESTABLE1(C1, C2)
    JOIN (VALUES (3, 2), (1, 2),
    (0, 3)) AS VALUESTABLE2(c1, c2)
    ON VALUESTABLE1.c1 = VALUESTABLE2.c1
    -- This results in:
    -- C1         |C2         |C1         |2
    -- -----------------------------------------------
    -- 3          |4          |3          |2
    -- 1          |5          |1          |2

    -- List every department with the employee number and
    -- last name of the manager

    SELECT DEPTNO, DEPTNAME, EMPNO, LASTNAME
    	FROM DEPARTMENT INNER JOIN EMPLOYEE
    	ON MGRNO = EMPNO

    -- List every employee number and last name
    -- with the employee number and last name of their manager
    SELECT E.EMPNO, E.LASTNAME, M.EMPNO, M.LASTNAME
    	FROM EMPLOYEE E INNER JOIN
    	DEPARTMENT INNER JOIN EMPLOYEE M
            ON MGRNO = M.EMPNO
            ON E.WORKDEPT = DEPTNO

LEFT OUTER JOIN operation
A LEFT OUTER JOIN is one of the JOIN operations that allow you to specify a join clause. It preserves the unmatched rows from the first (left) table, joining them with a NULL row in the shape of the second (right) table.
Syntax

    TableExpression LEFT [ OUTER ] JOIN TableExpression
    {
        ON booleanExpression
        }

The scope of expressions in either the ON clause includes the current tables and any tables in query blocks outer to the current SELECT. The ON clause can reference tables not being joined and does not have to reference either of the tables being joined (though typically it does).
Example 1

    --match cities to countries in Asia

    SELECT CITIES.COUNTRY, CITIES.CITY_NAME, REGION
    FROM Countries
    LEFT OUTER JOIN Cities
    ON CITIES.COUNTRY_ISO_CODE = COUNTRIES.COUNTRY_ISO_CODE
    WHERE REGION = 'Asia'

    -- use the synonymous syntax, LEFT JOIN, to achieve exactly
    -- the same results as in the example above

    SELECT  COUNTRIES.COUNTRY, CITIES.CITY_NAME,REGION
    FROM COUNTRIES
    LEFT JOIN CITIES
    ON CITIES.COUNTRY_ISO_CODE = COUNTRIES.COUNTRY_ISO_CODE
    WHERE REGION = 'Asia'

Example 2

    -- Join the EMPLOYEE and DEPARTMENT tables,
    -- select the employee number (EMPNO),
    -- employee surname (LASTNAME),
    -- department number (WORKDEPT in the EMPLOYEE table
    -- and DEPTNO in the DEPARTMENT table)
    -- and department name (DEPTNAME)
    -- of all employees who were born (BIRTHDATE) earlier than 1930

    SELECT EMPNO, LASTNAME, WORKDEPT, DEPTNAME
       FROM SAMP.EMPLOYEE LEFT OUTER JOIN SAMP.DEPARTMENT
       ON WORKDEPT = DEPTNO
       AND YEAR(BIRTHDATE) < 1930

    -- List every department with the employee number and
    -- last name of the manager,
    -- including departments without a manager

    SELECT DEPTNO, DEPTNAME, EMPNO, LASTNAME
          FROM DEPARTMENT LEFT OUTER JOIN EMPLOYEE
    	    ON MGRNO = EMPNO

RIGHT OUTER JOIN operation
A RIGHT OUTER JOIN is one of the JOIN operations that allow you to specify a JOIN clause. It preserves the unmatched rows from the second (right) table, joining them with a NULL in the shape of the first (left) table. A LEFT OUTER JOIN B is equivalent to B RIGHT OUTER JOIN A, with the columns in a different order.
Syntax

    TableExpression RIGHT [ OUTER ] JOIN TableExpression
    {
        ON booleanExpression
        }

The scope of expressions in the ON clause includes the current tables and any tables in query blocks outer to the current SELECT. The ON clause can reference tables not being joined and does not have to reference either of the tables being joined (though typically it does).
Example 1

    -- get all countries and corresponding cities, including
    -- countries without any cities

    SELECT COUNTRIES.COUNTRY, CITIES.CITY_NAME
    FROM CITIES
    RIGHT OUTER JOIN COUNTRIES
    ON CITIES.COUNTRY_ISO_CODE = COUNTRIES.COUNTRY_ISO_CODE

    -- get all countries in Africa and corresponding cities, including
    -- countries without any cities

    SELECT COUNTRIES.COUNTRY, CITIES.CITY_NAME
    FROM CITIES
    RIGHT OUTER JOIN COUNTRIES
    ON CITIES.COUNTRY_ISO_CODE = COUNTRIES.COUNTRY_ISO_CODE
    WHERE Countries.region = 'Africa'

    -- use the synonymous syntax, RIGHT JOIN, to achieve exactly
    -- the same results as in the example above

    SELECT COUNTRIES.COUNTRY, CITIES.CITY_NAME
    FROM CITIES
    RIGHT JOIN COUNTRIES
    ON CITIES.COUNTRY_ISO_CODE = COUNTRIES.COUNTRY_ISO_CODE
    WHERE Countries.region = 'Africa'

Example 2

    -- a TableExpression can be a joinOperation. Therefore
    -- you can have multiple join operations in a FROM clause
    -- List every employee number and last name
    -- with the employee number and last name of their manager

    SELECT E.EMPNO, E.LASTNAME, M.EMPNO, M.LASTNAME
    	FROM EMPLOYEE E RIGHT OUTER JOIN
    	DEPARTMENT RIGHT OUTER JOIN EMPLOYEE M
            ON MGRNO = M.EMPNO
            ON E.WORKDEPT = DEPTNO

SQL queries
Query
A query creates a virtual table based on existing tables or constants built into tables.
Syntax

    {
        ( Query ) |
        Query INTERSECT [ ALL | DISTINCT ] Query |
        Query EXCEPT [ ALL | DISTINCT ] Query |
        Query UNION [ ALL | DISTINCT ] Query |
    SelectExpression | VALUES Expression
    }

You can arbitrarily put parentheses around queries, or use the parentheses to control the order of evaluation of the INTERSECT, EXCEPT, or UNION operations. These operations are evaluated from left to right when no parentheses are present, with the exception of INTERSECT operations, which would be evaluated before any UNION or EXCEPT operations.
Duplicates in UNION, INTERSECT, and EXCEPT ALL results
The ALL and DISTINCT keywords determine whether duplicates are eliminated from the result of the operation. If you specify the DISTINCT keyword, then the result will have no duplicate rows. If you specify the ALL keyword, then there may be duplicates in the result, depending on whether there were duplicates in the input. DISTINCT is the default, so if you don't specify ALL or DISTINCT, the duplicates will be eliminated. For example, UNION builds an intermediate ResultSet with all of the rows from both queries and eliminates the duplicate rows before returning the remaining rows. UNION ALL returns all rows from both queries as the result.
Depending on which operation is specified, if the number of copies of a row in the left table is L and the number of copies of that row in the right table is R, then the number of duplicates of that particular row that the output table contains (assuming the ALL keyword is specified) is:

• |  | UNION: ( L + R ).
• |  | EXCEPT: the maximum of ( L – R ) and 0 (zero).
• |  | INTERSECT: the minimum of L and R.

Examples

    -- a Select expression
    SELECT *
    FROM ORG

    -- a subquery
    SELECT *
    FROM (SELECT CLASS_CODE FROM CL_SCHED) AS CS

    -- a subquery
    SELECT *
    FROM (SELECT CLASS_CODE FROM CL_SCHED) AS CS (CLASS_CODE)

    -- a UNION
    -- returns all rows from columns DEPTNUMB and MANAGER
    -- in table ORG
    -- and (1,2) and (3,4)
    -- DEPTNUMB and MANAGER are smallint columns
    SELECT DEPTNUMB, MANAGER
    FROM ORG
    UNION ALL
    VALUES (1,2), (3,4)

    -- a values expression
    VALUES (1,2,3)
    -- List the employee numbers (EMPNO) of all employees in the EMPLOYEE table
    -- whose department number (WORKDEPT) either begins with 'E' or
    -- who are assigned to projects in the EMP_ACT table
    -- whose project number (PROJNO) equals 'MA2100', 'MA2110', or 'MA2112'
    SELECT EMPNO
         FROM EMPLOYEE
         WHERE WORKDEPT LIKE 'E%'
      UNION
      SELECT EMPNO
         FROM EMP_ACT
         WHERE PROJNO IN('MA2100', 'MA2110', 'MA2112')
    -- Make the same query as in the previous example
    -- and "tag" the rows from the EMPLOYEE table with 'emp' and
    -- the rows from the EMP_ACT table with 'emp_act'.
    -- Unlike the result from the previous example,
    -- this query may return the same EMPNO more than once,
    -- identifying which table it came from by the associated "tag"
    SELECT EMPNO, 'emp'
         FROM EMPLOYEE
         WHERE WORKDEPT LIKE 'E%'
      UNION
      SELECT EMPNO, 'emp_act' FROM EMP_ACT
         WHERE PROJNO IN('MA2100', 'MA2110', 'MA2112')
    -- Make the same query as in the previous example,
    -- only use UNION ALL so that no duplicate rows are eliminated
    SELECT EMPNO
          FROM EMPLOYEE
          WHERE WORKDEPT LIKE 'E%'
      UNION ALL
      SELECT EMPNO
         FROM EMP_ACT
         WHERE PROJNO IN('MA2100', 'MA2110', 'MA2112')
    -- Make the same query as in the previous example,
    -- only include an additional two employees currently not in any table and
    -- tag these rows as "new"
     SELECT EMPNO, 'emp'
         FROM EMPLOYEE
         WHERE WORKDEPT LIKE 'E%'
      UNION
      SELECT EMPNO, 'emp_act'
         FROM EMP_ACT
         WHERE PROJNO IN('MA2100', 'MA2110', 'MA2112')
      UNION
         VALUES ('NEWAAA', 'new'), ('NEWBBB', 'new')

ScalarSubquery
You can place a ScalarSubquery anywhere an Expression is permitted. A ScalarSubquery turns a SelectExpression result into a scalar value because it returns only a single row and column value.
The query must evaluate to a single row with a single column.
Sometimes also called an expression subquery.
Syntax

    (Query)

Examples

    -- avg always returns a single value, so the subquery is
    -- a ScalarSubquery
    SELECT NAME, COMM
      FROM STAFF
      WHERE EXISTS
        (SELECT AVG(BONUS + 800)
           FROM EMPLOYEE
           WHERE COMM < 5000
           AND EMPLOYEE.LASTNAME = UPPER(STAFF.NAME)
    )
    -- Introduce a way of "generating" new data values,
    -- using a query which selects from a VALUES clause (which is an
    -- alternate form of a fullselect).
    -- This query shows how a table can be derived called "X" having
    -- 2 columns "R1" and "R2" and 1 row of data.
    SELECT R1,R2
    	FROM (VALUES('GROUP 1','GROUP 2')) AS X(R1,R2)

TableSubquery
A TableSubquery is a subquery that returns multiple rows.
Unlike a ScalarSubquery, a TableSubquery is allowed only:

• |  | as a TableExpression in a FROM clause
• |  | with EXISTS, IN, or quantified comparisons.

When used as a TableExpression in a FROM clause, it can return multiple columns. When used with EXISTS, it returns multiple columns only if you use * to return the multiple columns.
When used with IN or quantified comparisons, it must return a single column.
Syntax

    (Query)

Example

    -- a subquery used as a TableExpression in a FROM clause
    SELECT VirtualFlightTable.flight_ID
    FROM
        (SELECT flight_ID, orig_airport, dest_airport
        FROM Flights
        WHERE (orig_airport = 'SFO' OR dest_airport = 'SCL') )
    AS VirtualFlightTable
    -- a subquery (values expression) used as a TableExpression
    -- in a FROM clause
    SELECT mycol1
    FROM
        (VALUES (1, 2), (3, 4))
    AS mytable (mycol1, mycol2)
    -- a subquery used with EXISTS
    SELECT *
    FROM Flights
    WHERE EXISTS
        (SELECT * FROM Flights WHERE dest_airport = 'SFO'
        AND orig_airport = 'GRU')
    -- a subquery used with IN
    SELECT flight_id, segment_number
    FROM Flights
    WHERE flight_id IN
        (SELECT flight_ID
        FROM Flights WHERE orig_airport = 'SFO'
        OR dest_airport = 'SCL')
    -- a subquery used with a quantified comparison
    SELECT NAME, COMM
    FROM STAFF
    WHERE COMM >
    (SELECT AVG(BONUS + 800)
         FROM EMPLOYEE
         WHERE COMM < 5000)

Built-in functions
A built-in function is an expression in which an SQL keyword or special operator executes some operation. Built-in functions use keywords or special built-in operators. Built-ins are SQL92Identifiers and are case-insensitive. Note that escaped functions like TIMESTAMPADD and TIMESTAMPDIFF are only accessible using the JDBC escape function syntax, and can be found in JDBC escape syntax.
Standard built-in functions
The standard built-in functions supported in Derby are as follows:

• |  | ABS or ABSVAL function
• |  | ACOS function
• |  | ASIN function
• |  | ATAN function
• |  | BIGINT function
• |  | CAST function
• |  | CEIL or CEILING function
• |  | CHAR function
• |  | Concatenation operator
• |  | COS function
• |  | NULLIF expressions
• |  | CURRENT_DATE function
• |  | CURRENT ISOLATION function
• |  | CURRENT_TIME function
• |  | CURRENT_TIMESTAMP function
• |  | CURRENT_USER function
• |  | DATE function
• |  | DAY function
• |  | DEGREES function
• |  | DOUBLE function
• |  | EXP function
• |  | FLOOR function
• |  | HOUR function
• |  | IDENTITY_VAL_LOCAL function
• |  | INTEGER function
• |  | LENGTH function
• |  | LN or LOG function
• |  | LOG10 function
• |  | LOCATE function
• |  | LCASE or LOWER function
• |  | LTRIM function
• |  | MINUTE function
• |  | MOD function
• |  | MONTH function
• |  | PI function
• |  | RADIANS function
• |  | RTRIM function
• |  | SECOND function
• |  | SESSION_USER function
• |  | SIN function
• |  | SMALLINT function
• |  | SQRT function
• |  | SUBSTR function
• |  | TAN function
• |  | TIME function
• |  | TIMESTAMP function
• |  | TRIM function
• |  | UCASE or UPPER function
• |  | USER function
• |  | VARCHAR function
• |  | YEAR function

Aggregates (set functions)
This section describes aggregates (also described as set functions in ANSI SQL-92 and as column functions in some database literature). They provide a means of evaluating an expression over a set of rows. Whereas the other built-in functions operate on a single expression, aggregates operate on a set of values and reduce them to a single scalar value. Built-in aggregates can calculate the minimum, maximum, sum, count, and average of an expression over a set of values as well as count rows. You can also create your own aggregates to perform other set functions such as calculating the standard deviation.
The built-in aggregates can operate on the data types shown in Permitted Data Types for Built-in Aggregates.
Table 7. Permitted Data Types for Built-in Aggregates

' | All Types | Numeric Built-in Data Types
COUNT | X | X
MIN | ' | X
MAX | ' | X
AVG | ' | X
SUM | ' | X

Aggregates are permitted only in the following:

• |  | A SelectItem in a SelectExpression.
• |  | A HAVING clause.
• |  | An ORDER BY clause (using an alias name) if the aggregate appears in the result of the relevant query block. That is, an alias for an aggregate is permitted in an ORDER BY clause if and only if the aggregate appears in a SelectItem in a SelectExpression.

All expressions in SelectItems in the SelectExpression must be either aggregates or grouped columns (see GROUP BY clause). (The same is true if there is a HAVING clause without a GROUP BY clause.) This is because the ResultSet of a SelectExpression must be either a scalar (single value) or a vector (multiple values), but not a mixture of both. (Aggregates evaluate to a scalar value, and the reference to a column can evaluate to a vector.) For example, the following query mixes scalar and vector values and thus is not valid:

    -- not valid
    SELECT MIN(flying_time), flight_id
    FROM Flights

Aggregates are not allowed on outer references (correlations). This means that if a subquery contains an aggregate, that aggregate cannot evaluate an expression that includes a reference to a column in the outer query block. For example, the following query is not valid because SUM operates on a column from the outer query:

    SELECT c1
    FROM t1
    GROUP BY c1
    HAVING c2 >
        (SELECT t2.x
        FROM t2
        WHERE t2.y = SUM(t1.c3))

A cursor declared on a ResultSet that includes an aggregate in the outer query block is not updatable.
This section includes the following aggregates:

• |  | AVG function
• |  | COUNT function
• |  | MAX function
• |  | MIN function
• |  | SUM function

ABS or ABSVAL function
ABS or ABSVAL returns the absolute value of a numeric expression. The return type is the type of parameter. All built-in numeric types are supported (DECIMAL, DOUBLE PRECISION, FLOAT, INTEGER, BIGINT, NUMERIC, REAL, and SMALLINT).
Syntax

    ABS(NumericExpression)

    -- returns 3
    VALUES ABS(-3)

ACOS function
The ACOS function returns the arc cosine of a specified number.
The specified number is the cosine, in radians, of the angle that you want. The specified number must be a DOUBLE PRECISION number.

• |  | If the specified number is NULL, the result of this function is NULL.
• |  | If the absolute value of the specified number is greater than 1, an exception is returned that indicates that the value is out of range (SQL state 22003).

The returned value, in radians, is in the range of zero (0) to pi. The data type of the returned value is a DOUBLE PRECISION number.
Syntax

    ACOS ( number )

ASIN function
The ASIN function returns the arc sine of a specified number.
The specified number is the sine, in radians, of the angle that you want. The specified number must be a DOUBLE PRECISION number.

• |  | If the specified number is NULL, the result of this function is NULL.
• |  | If the specified number is zero (0), the result of this function is zero with the same sign as the specified number.
• |  | If the absolute value of the specified number is greater than 1, an exception is returned that indicates that the value is out of range (SQL state 22003).

The returned value, in radians, is in the range -pi/2 to pi/2. The data type of the returned value is a DOUBLE PRECISION number.
Syntax

    ASIN ( number )

ATAN function
The ATAN function returns the arc tangent of a specified number.
The specified number is the tangent, in radians, of the angle that you want. The specified number must be a DOUBLE PRECISION number.

• |  | If the specified number is NULL, the result of this function is NULL.
• |  | If the specified number is zero (0), the result of this function is zero with the same sign as the specified number.

The returned value, in radians, is in the range -pi/2 to pi/2. The data type of the returned value is a DOUBLE PRECISION number.
Syntax

    ATAN ( number )

AVG function
AVG is an aggregate function that evaluates the average of an expression over a set of rows (see Aggregates (set functions)). AVG is allowed only on expressions that evaluate to numeric data types.
Syntax

    AVG ( [ DISTINCT | ALL ] Expression )

The DISTINCT qualifier eliminates duplicates. The ALL qualifier retains duplicates. ALL is the default value if neither ALL nor DISTINCT is specified. For example, if a column contains the values 1.0, 1.0, 1.0, 1.0, and 2.0, AVG(col) returns a smaller value than AVG(DISTINCT col).
Only one DISTINCT aggregate expression per SelectExpression is allowed. For example, the following query is not valid:

    SELECT AVG (DISTINCT flying_time), SUM (DISTINCT miles)
    FROM Flights

The expression can contain multiple column references or expressions, but it cannot contain another aggregate or subquery. It must evaluate to an SQL-92 numeric data type. You can therefore call methods that evaluate to SQL-92 data types. If an expression evaluates to NULL, the aggregate skips that value.
The resulting data type is the same as the expression on which it operates (it will never overflow). The following query, for example, returns the INTEGER 1, which might not be what you would expect:

    SELECT AVG(c1)
    FROM (VALUES (1), (1), (1), (1), (2)) AS myTable (c1)

CAST the expression to another data type if you want more precision:

    SELECT AVG(CAST (c1 AS DOUBLE PRECISION))
    FROM (VALUES (1), (1), (1), (1), (2)) AS myTable (c1)

BIGINT function
The BIGINT function returns a 64-bit integer representation of a number or character string in the form of an integer constant.
Syntax

    BIGINT (CharacterExpression | NumericExpression )

CharacterExpression
An expression that returns a character string value of length not greater than the maximum length of a character constant. Leading and trailing blanks are eliminated and the resulting string must conform to the rules for forming an SQL integer constant. The character string cannot be a long string. If the argument is a CharacterExpression, the result is the same number that would occur if the corresponding integer constant were assigned to a big integer column or variable.
NumericExpression
An expression that returns a value of any built-in numeric data type. If the argument is a NumericExpression, the result is the same number that would occur if the argument were assigned to a big integer column or variable. If the whole part of the argument is not within the range of integers, an error occurs. The decimal part of the argument is truncated if present.
The result of the function is a big integer. If the argument can be null, the result can be null; if the argument is null, the result is the null value.
Using the EMPLOYEE table, select the EMPNO column in big integer form for further processing in the application:

    SELECT BIGINT (EMPNO) FROM EMPLOYEE

CASE expressions
Use the CASE expressions for conditional expressions in Derby.
CASE expression syntax
You can place a CASE expression anywhere an expression is allowed. It chooses an expression to evaluate based on a boolean test.

    CASE
      WHEN booleanExpression THEN thenExpression
      [ WHEN booleanExpression THEN thenExpression ]...
      ELSE elseExpression
    END

ThenExpression and elseExpression are both expressions that must be type-compatible. For built-in types, this means that the types must be the same or a built-in broadening conversion must exist between the types.

    -- returns 3
    VALUES CASE WHEN 1=1 THEN 3 ELSE 4 END

    -- returns 7
    VALUES
       CASE
          WHEN 1 = 2 THEN 3
          WHEN 4 = 5 THEN 6
          ELSE 7
       END

CAST function
The CAST function converts a value from one data type to another and provides a data type to a dynamic parameter (?) or a NULL value.
CAST expressions are permitted anywhere expressions are permitted.
Syntax

    CAST ( [ Expression | NULL | ? ]
        AS Datatype)

The data type to which you are casting an expression is the target type. The data type of the expression from which you are casting is the source type.
CAST conversions among SQL-92 data types
The following table shows valid explicit conversions between source types and target types for SQL data types. This table shows which explicit conversions between data types are valid. The first column on the table lists the source data types. The first row lists the target data types. A "Y" indicates that a conversion from the source to the target is valid. For example, the first cell in the second row lists the source data type SMALLINT. The remaining cells on the second row indicate the whether or not you can convert SMALLINT to the target data types that are listed in the first row of the table.
Table 8. Explicit conversions between source types and target types for SQL data types

Types |
    S
    M
    A
    L
    L
    I
    N
    T
    I
    N
    T
    E
    G
    E
    R
    B
    I
    G
    I
    N
    T
    D
    E
    C
    I
    M
    A
    L
    R
    E
    A
    L
    D
    O
    U
    B
    L
    E
    F
    L
    O
    A
    T
    C
    H
    A
    R
    V
    A
    R
    C
    H
    A
    R
    L
    O
    N
    G

    V
    A
    R
    C
    H
    A
    R
    C
    H
    A
    R

    F
    O
    R

    B
    I
    T

    D
    A
    T
    A
    V
    A
    R
    C
    H
    A
    R

    F
    O
    R

    B
    I
    T

    D
    A
    T
    A
    L
    O
    N
    G

    V
    A
    R
    C
    H
    A
    R

    F
    O
    R

    B
    I
    T

    D
    A
    T
    A
    C
    L
    O
    B
    B
    L
    O
    B
    D
    A
    T
    E
    T
    I
    M
    E
    T
    I
    M
    E
    S
    T
    A
    M
    P
    X
    M
    L
SMALLINT | Y | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | -
INTEGER | Y | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | -
BIGINT | Y | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | -
DECIMAL | Y | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | -
REAL | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
DOUBLE | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
FLOAT | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
CHAR | Y | Y | Y | Y | - | - | - | Y | Y | Y | - | - | - | Y | - | Y | Y | Y | -
VARCHAR | Y | Y | Y | Y | - | - | - | Y | Y | Y | - | - | - | Y | - | Y | Y | Y | -
LONG VARCHAR | - | - | - | - | - | - | - | Y | Y | Y | - | - | - | Y | - | - | - | - | -
CHAR FOR BIT DATA | - | - | - | - | - | - | - | - | - | - | Y | Y | Y | Y | Y | - | - | - | -
VARCHAR FOR BIT DATA | - | - | - | - | - | - | - | - | - | - | Y | Y | Y | Y | Y | - | - | - | -
LONG VARCHAR FOR BIT DATA | - | - | - | - | - | - | - | - | - | - | Y | Y | Y | Y | Y | - | - | - | -
CLOB | - | - | - | - | - | - | - | Y | Y | Y | - | - | - | Y | - | - | - | - | -
BLOB | - | - | - | - | - | - | - | - | - | - | - | - | - | - | Y | - | - | - | -
DATE | - | - | - | - | - | - | - | Y | Y | - | - | - | - | - | - | Y | - | - | -
TIME | - | - | - | - | - | - | - | Y | Y | - | - | - | - | - | - | - | Y | - | -
TIMESTAMP | - | - | - | - | - | - | - | Y | Y | - | - | - | - | - | - | Y | Y | Y | -
XML | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | Y

If a conversion is valid, CASTs are allowed. Size incompatibilities between the source and target types might cause runtime errors.
Notes
In this discussion, the Derby SQL-92 data types are categorized as follows:

• |  | numeric
• |  | Exact numeric (SMALLINT, INTEGER, BIGINT, DECIMAL, NUMERIC)
• |  | Approximate numeric (FLOAT, REAL, DOUBLE PRECISION)
• |  | string
• |  | Character string (CLOB, CHAR, VARCHAR, LONG VARCHAR)
• |  | Bit string (BLOB, CHAR FOR BIT DATA, VARCHAR FOR BIT DATA, LONG VARCHAR FOR BIT DATA)
• |  | date/time
• |  | DATE
• |  | TIME
• |  | TIMESTAMP

Conversions from numeric types
A numeric type can be converted to any other numeric type. If the target type cannot represent the non-fractional component without truncation, an exception is raised. If the target numeric cannot represent the fractional component (scale) of the source numeric, then the source is silently truncated to fit into the target. For example, casting 763.1234 as INTEGER yields 763.
Conversions from and to bit strings
Bit strings can be converted to other bit strings, but not character strings. Strings that are converted to bit strings are padded with trailing zeros to fit the size of the target bit string. The BLOB type is more limited and requires explicit casting. In most cases the BLOB type cannot be casted to and from other types.
Conversions of date/time values
A date/time value can always be converted to and from a TIMESTAMP. If a DATE is converted to a TIMESTAMP, the TIME component of the resulting TIMESTAMP is always 00:00:00. If a TIME data value is converted to a TIMESTAMP, the DATE component is set to the value of CURRENT_DATE at the time the CAST is executed. If a TIMESTAMP is converted to a DATE, the TIME component is silently truncated. If a TIMESTAMP is converted to a TIME, the DATE component is silently truncated.

    SELECT CAST (miles AS INT)
    FROM Flights
    -- convert timestamps to text
    INSERT INTO mytable (text_column)
    VALUES (CAST (CURRENT_TIMESTAMP AS VARCHAR(100)))
    -- you must cast NULL as a data type to use it
    SELECT airline
    FROM Airlines
    UNION ALL
    VALUES (CAST (NULL AS CHAR(2)))
    -- cast a double as a decimal
    SELECT CAST (FLYING_TIME AS DECIMAL(5,2))
    FROM FLIGHTS
    -- cast a SMALLINT to a BIGINT
    VALUES CAST (CAST (12 as SMALLINT) as BIGINT)

Conversions of XML values
An XML value cannot be converted to any non-XML type using an explicit or implicit CAST. Use the XMLSERIALIZE operator to convert an XML type to a character type.
CEIL or CEILING function
The CEIL and CEILING functions round the specified number up, and return the smallest number that is greater than or equal to the specified number.
The specified number must be a DOUBLE PRECISION number.

• |  | If the specified number is NULL, the result of these functions is NULL.
• |  | If the specified number is equal to a mathematical integer, the result of these functions is the same as the specified number.
• |  | If the specified number is zero (0), the result of these functions is zero.
• |  | If the specified number is less than zero but greater than -1.0, then the result of these functions is zero.

The returned value is the smallest (closest to negative infinity) double floating point value that is greater than or equal to the specified number. The returned value is equal to a mathematical integer. The data type of the returned value is a DOUBLE PRECISION number.
Syntax

    CEIL ( number )

    CEILING ( number )

CHAR function
The CHAR function returns a fixed-length character string representation.
The representations are:

• |  | A character string, if the first argument is any type of character string.
• |  | A datetime value, if the first argument is a date, time, or timestamp.
• |  | A decimal number, if the first argument is a decimal number.
• |  | A double-precision floating-point number, if the first argument is a DOUBLE or REAL.
• |  | An integer number, if the first argument is a SMALLINT, INTEGER, or BIGINT.

The first argument must be of a built-in data type. The result of the CHAR function is a fixed-length character string. If the first argument can be null, the result can be null. If the first argument is null, the result is the null value. The first argument cannot be an XML value. To convert an XML value to a CHAR of a specified length, you must use the SQL/XML serialization operator XMLSERIALIZE.
Character to character syntax

    CHAR (CharacterExpression [, integer] )

CharacterExpression
An expression that returns a value that is CHAR, VARCHAR, LONG VARCHAR, or CLOB data type.
integer
The length attribute for the resulting fixed length character string. The value must be between 0 and 254.
If the length of the character-expression is less than the length attribute of the result, the result is padded with blanks up to the length of the result. If the length of the character-expression is greater than the length attribute of the result, truncation is performed. A warning is returned unless the truncated characters were all blanks and the character-expression was not a long string (LONG VARCHAR or CLOB).
Integer to character syntax

    CHAR (IntegerExpression )

IntegerExpression
An expression that returns a value that is an integer data type (either SMALLINT, INTEGER or BIGINT).
The result is the character string representation of the argument in the form of an SQL integer constant. The result consists of n characters that are the significant digits that represent the value of the argument with a preceding minus sign if the argument is negative. It is left justified.

• |  | If the first argument is a small integer: The length of the result is 6. If the number of characters in the result is less than 6, then the result is padded on the right with blanks to length 6.
• |  | If the first argument is a large integer: The length of the result is 11. If the number of characters in the result is less than 11, then the result is padded on the right with blanks to length 11.
• |  | If the first argument is a big integer: The length of the result is 20. If the number of characters in the result is less than 20, then the result is padded on the right with blanks to length 20.

Datetime to character syntax

    CHAR (DatetimeExpression )

DatetimeExpression
An expression that is one of the following three data types:

• |  | date: The result is the character representation of the date. The length of the result is 10.
• |  | time: The result is the character representation of the time. The length of the result is 8.
• |  | timestamp: The result is the character string representation of the timestamp. The length of the result is 26.

Decimal to character

    CHAR (DecimalExpression )

DecimalExpression
An expression that returns a value that is a decimal data type. If a different precision and scale is desired, the DECIMAL scalar function can be used first to make the change.
Floating point to character syntax

    CHAR (FloatingPointExpression )

FloatingPointExpression
An expression that returns a value that is a floating-point data type (DOUBLE or REAL).
Use the CHAR function to return the values for EDLEVEL (defined as smallint) as a fixed length character string:

    SELECT CHAR(EDLEVEL) FROM EMPLOYEE

An EDLEVEL of 18 would be returned as the CHAR(6) value '18 ' (18 followed by four blanks).
Concatenation operator
The concatenation operator, ||, concatenates its right operand to the end of its left operand. It operates on a character or bit expression.
Because all built-in data types are implicitly converted to strings, this function can act on all built-in data types.
Syntax

    {
        { CharacterExpression || CharacterExpression } |
        { BitExpression || BitExpression }
    }

For character strings, if both the left and right operands are of type CHAR, the resulting type is CHAR; otherwise, it is VARCHAR. The normal blank padding/trimming rules for CHAR and VARCHAR apply to the result of this operator.
The length of the resulting string is the sum of the lengths of both operands.
For bit strings, if both the left and the right operands are of type CHAR FOR BIT DATA, the resulting type is CHAR FOR BIT DATA; otherwise, it is VARCHAR FOR BIT DATA.

    --returns 'supercalifragilisticexbealidocious(sp?)'
    VALUES 'supercalifragilistic' || 'exbealidocious' || '(sp?)'
    -- returns NULL
    VALUES CAST (null AS VARCHAR(7))|| 'AString'
    -- returns '130asdf'
    VALUES '130' || 'asdf'

COS function
The COS function returns the cosine of a specified number.
The specified number is the angle, in radians, that you want the cosine for. The specified number must be a DOUBLE PRECISION number.

• |  | If the specified number is NULL, the result of this function is NULL.

Syntax

    COS ( number )

COUNT function
COUNT is an aggregate function that counts the number of rows accessed in an expression (see Aggregates (set functions)). COUNT is allowed on all types of expressions.
Syntax

    COUNT ( [ DISTINCT | ALL ] Expression )

The DISTINCT qualifier eliminates duplicates. The ALL qualifier retains duplicates. ALL is assumed if neither ALL nor DISTINCT is specified. For example, if a column contains the values 1, 1, 1, 1, and 2, COUNT(col) returns a greater value than COUNT(DISTINCT col).
Only one DISTINCT aggregate expression per SelectExpression is allowed. For example, the following query is not allowed:

    -- query not allowed
    SELECT COUNT (DISTINCT flying_time), SUM (DISTINCT miles)
    FROM Flights

An Expression can contain multiple column references or expressions, but it cannot contain another aggregate or subquery. If an Expression evaluates to NULL, the aggregate is not processed for that value.
The resulting data type of COUNT is INTEGER.

    -- Count the number of countries in each region,
    -- show only regions that have at least 2
    SELECT COUNT (country), region
    FROM Countries
    GROUP BY region
    HAVING COUNT (country) > 1

COUNT(*) function
COUNT(*) is an aggregate function that counts the number of rows accessed. No NULLs or duplicates are eliminated. COUNT(*) does not operate on an expression.
Syntax

    COUNT(*)

The resulting data type is INTEGER.

    -- Count the number of rows in the Flights table
    SELECT COUNT(*)
    FROM Flights

CURRENT DATE function
CURRENT DATE is a synonym for CURRENT_DATE.
CURRENT_DATE function
CURRENT_DATE returns the current date; the value returned does not change if it is executed more than once in a single statement. This means the value is fixed even if there is a long delay between fetching rows in a cursor.
Syntax

    CURRENT_DATE

or, alternately

    CURRENT DATE

    -- find available future flights:
    SELECT * FROM Flightavailability where flight_date > CURRENT_DATE;

CURRENT ISOLATION function
CURRENT ISOLATION returns the current isolation level as a char(2) value of either ""(blank), "UR", "CS", "RS", or "RR".
Syntax

    CURRENT ISOLATION

    VALUES CURRENT ISOLATION

CURRENT SCHEMA function
CURRENT SCHEMA returns the schema name used to qualify unqualified database object references.
Note: CURRENT SCHEMA and CURRENT SQLID are synonyms.
These functions return a string of up to 128 characters.
Syntax

    CURRENT SCHEMA

    -- or, alternately:

    CURRENT SQLID

    -- Set the name column default to the current schema:
    CREATE TABLE mytable (id int, name VARCHAR(128) DEFAULT CURRENT SQLID)
    -- Inserts default value of current schema value into the table:
    INSERT INTO mytable(id) VALUES (1)
    -- Returns the rows with the same name as the current schema:
    SELECT name FROM mytable WHERE name = CURRENT SCHEMA

CURRENT TIME function
CURRENT TIME is a synonym for CURRENT_TIME.
CURRENT_TIME function
CURRENT_TIME returns the current time; the value returned does not change if it is executed more than once in a single statement. This means the value is fixed even if there is a long delay between fetching rows in a cursor.
Syntax

    CURRENT_TIME

or, alternately

    CURRENT TIME

    VALUES CURRENT_TIME
    -- or, alternately:

    VALUES CURRENT TIME

CURRENT TIMESTAMP function
CURRENT TIMESTAMP is a synonym for CURRENT_TIMESTAMP.
CURRENT_TIMESTAMP function
CURRENT_TIMESTAMP returns the current timestamp; the value returned does not change if it is executed more than once in a single statement. This means the value is fixed even if there is a long delay between fetching rows in a cursor.
Syntax

    CURRENT_TIMESTAMP

or, alternately

    CURRENT TIMESTAMP

    VALUES CURRENT_TIMESTAMP
    -- or, alternately:

    VALUES CURRENT TIMESTAMP

CURRENT_USER function
CURRENT_USER returns the authorization identifier of the current user (the name of the user passed in when the user connected to the database). If there is no current user, it returns APP.
USER and SESSION_USER are synonyms.
These functions return a string of up to 128 characters.
Syntax

    CURRENT_USER

    VALUES CURRENT_USER

DATE function
The DATE function returns a date from a value.
The argument must be a date, timestamp, a positive number less than or equal to 2,932,897, a valid string representation of a date or timestamp, or a string of length 7 that is not a CLOB, LONG VARCHAR, or XML value. If the argument is a string of length 7, it must represent a valid date in the form yyyynnn, where yyyy are digits denoting a year, and nnn are digits between 001 and 366, denoting a day of that year. The result of the function is a date. If the argument can be null, the result can be null; if the argument is null, the result is the null value.
The other rules depend on the data type of the argument specified:

• |  | If the argument is a date, timestamp, or valid string representation of a date or timestamp: The result is the date part of the value.
• |  | If the argument is a number: The result is the date that is n-1 days after January 1, 0001, where n is the integral part of the number.
• |  | If the argument is a string with a length of 7: The result is the date represented by the string.

Syntax

    DATE ( expression )

This example results in an internal representation of '1988-12-25'.

    VALUES DATE('1988-12-25')

DAY function
The DAY function returns the day part of a value.
The argument must be a date, timestamp, or a valid character string representation of a date or timestamp that is not a CLOB, LONG VARCHAR, or XML value. The result of the function is an integer between 1 and 31. If the argument can be null, the result can be null; if the argument is null, the result is the null value.
Syntax

    DAY ( expression )

Example

    values day('2007-08-02');

The resulting value is 2.
DEGREES function
The DEGREES function converts a specified number from radians to degrees.
The specified number is an angle measured in radians, which is converted to an approximately equivalent angle measured in degrees. The specified number must be a DOUBLE PRECISION number.
Attention: The conversion from radians to degrees is not exact. You should not expect that the COS(RADIANS(90.0)) to exactly equal 0.0.
The data type of the returned value is a DOUBLE PRECISION number.
Syntax

    DEGREES ( number )

DOUBLE function
The DOUBLE function returns a floating-point number corresponding to a:

• |  | number if the argument is a numeric expression.
• |  | character string representation of a number if the argument is a string expression.

Numeric to double

    DOUBLE [PRECISION] (NumericExpression )

NumericExpression
The argument is an expression that returns a value of any built-in numeric data type.
The result of the function is a double-precision floating-point number. If the argument can be null, the result can be null; if the argument is null, the result is the null value. The result is the same number that would occur if the argument were assigned to a double-precision floating-point column or variable.
Character string to double

    DOUBLE (StringExpression )

StringExpression
The argument can be of type CHAR or VARCHAR in the form of a numeric constant. Leading and trailing blanks in argument are ignored.
The result of the function is a double-precision floating-point number. The result can be null; if the argument is null, the result is the null value. The result is the same number that would occur if the string was considered a constant and assigned to a double-precision floating-point column or variable.
EXP function
The EXP function returns e raised to the power of the specified number.
The specified number is the exponent that you want to raise e to. The specified number must be a DOUBLE PRECISION number.
The constant e is the base of the natural logarithms.
The data type of the returned value is a DOUBLE PRECISION number.
Syntax

    EXP ( number )

FLOOR function
The FLOOR function rounds the specified number down, and returns the largest number that is less than or equal to the specified number.
The specified number must be a DOUBLE PRECISION number.

• |  | If the specified number is NULL, the result of this function is NULL.
• |  | If the specified number is equal to a mathematical integer, the result of this function is the same as the specified number.
• |  | If the specified number is zero (0), the result of this function is zero.

The returned value is the largest (closest to positive infinity) double floating point value that is less than or equal to the specified number. The returned value is equal to a mathematical integer. The data type of the returned value is a DOUBLE PRECISION number.
Syntax

    FLOOR ( number )

HOUR function
The HOUR function returns the hour part of a value.
The argument must be a time, timestamp, or a valid character string representation of a time or timestamp that is not a CLOB, LONG VARCHAR, or XML value. The result of the function is an integer between 0 and 24. If the argument can be null, the result can be null; if the argument is null, the result is the null value.
Syntax

    HOUR ( expression )

Example
Select all the classes that start in the afternoon from a table called TABLE1.

    SELECT * FROM TABLE1 WHERE HOUR(STARTING) BETWEEN 12 AND 17

IDENTITY_VAL_LOCAL function
Derby supports the IDENTITY_VAL_LOCAL function.
Syntax:

     IDENTITY_VAL_LOCAL ( )

The IDENTITY_VAL_LOCAL function is a non-deterministic function that returns the most recently assigned value of an identity column for a connection, where the assignment occurred as a result of a single row INSERT statement using a VALUES clause.
The IDENTITY_VAL_LOCAL function has no input parameters. The result is a DECIMAL (31,0), regardless of the actual data type of the corresponding identity column.
The value returned by the IDENTITY_VAL_LOCAL function, for a connection, is the value assigned to the identity column of the table identified in the most recent single row INSERT statement. The INSERT statement must contain a VALUES clause on a table containing an identity column. The assigned value is an identity value generated by Derby. The function returns a null value when a single row INSERT statement with a VALUES clause has not been issued for a table containing an identity column.
The result of the function is not affected by the following:

• |  | A single row INSERT statement with a VALUES clause for a table without an identity column
• |  | A multiple row INSERT statement with a VALUES clause
• |  | An INSERT statement with a fullselect

If a table with an identity column has an INSERT trigger defined that inserts into another table with another identity column, then the IDENTITY_VAL_LOCAL() function will return the generated value for the statement table, and not for the table modified by the trigger.
Examples:

    ij> create table t1(c1 int generated always as identity, c2 int);
    0 rows inserted/updated/deleted
    ij> insert into t1(c2) values (8);
    1 row inserted/updated/deleted
    ij> values IDENTITY_VAL_LOCAL();
    1
    -------------------------------
    1
    1 row selected
    ij> select IDENTITY_VAL_LOCAL()+1, IDENTITY_VAL_LOCAL()-1 from t1;
    1                                |2
    -------------------------------------------------------------------
    2                                |0
    1 row selected
    ij> insert into t1(c2) values (IDENTITY_VAL_LOCAL());
    1 row inserted/updated/deleted
    ij> select * from t1;
    C1             |C2
    -------------------------------
    1              |8
    2              |1
    2 rows selected
    ij> values IDENTITY_VAL_LOCAL();
    1
    -------------------------------
    2
    1 row selected
    ij> insert into t1(c2) values (8), (9);
    2 rows inserted/updated/deleted
    ij> -- multi-values insert, return value of the function should not change
    values IDENTITY_VAL_LOCAL();
    1
    -------------------------------
    2
    1 row selected
    ij> select * from t1;
    C1             |C2
    -------------------------------
    1              |8
    2              |1
    3              |8
    4              |9
    4 rows selected
    ij> insert into t1(c2) select c1 from t1;
    4 rows inserted/updated/deleted
    -- insert with sub-select, return value should not change
    ij> values IDENTITY_VAL_LOCAL();
    1
    -------------------------------
    2
    1 row selected
    ij> select * from t1;
    C1             |C2
    -------------------------------
    1              |8
    2              |1
    3              |8
    4              |9
    5              |1
    6              |2
    7              |3
    8              |4
    8 rows selected

INTEGER function
The INTEGER function returns an integer representation of a number, character string, date, or time in the form of an integer constant.
Syntax

    INT[EGER] (NumericExpression | CharacterExpression )

NumericExpression
An expression that returns a value of any built-in numeric data type. If the argument is a numeric-expression, the result is the same number that would occur if the argument were assigned to a large integer column or variable. If the whole part of the argument is not within the range of integers, an error occurs. The decimal part of the argument is truncated if present.
CharacterExpression
An expression that returns a character string value of length not greater than the maximum length of a character constant. Leading and trailing blanks are eliminated and the resulting string must conform to the rules for forming an SQL integer constant. The character string cannot be a long string. If the argument is a character-expression, the result is the same number that would occur if the corresponding integer constant were assigned to a large integer column or variable.
The result of the function is a large integer. If the argument can be null, the result can be null; if the argument is null, the result is the null value.
Using the EMPLOYEE table, select a list containing salary (SALARY) divided by education level (EDLEVEL). Truncate any decimal in the calculation. The list should also contain the values used in the calculation and employee number (EMPNO). The list should be in descending order of the calculated value:

    SELECT INTEGER (SALARY / EDLEVEL), SALARY, EDLEVEL, EMPNO
    FROM EMPLOYEE
    ORDER BY 1 DESC

LCASE or LOWER function
LCASE or LOWER takes a character expression as a parameter and returns a string in which all alpha characters have been converted to lowercase.
Syntax

    LCASE or LOWER ( CharacterExpression )

A CharacterExpression is a CHAR, VARCHAR, or LONG VARCHAR data type or any built-in type that is implicitly converted to a string (except a bit expression).
If the parameter type is CHAR or LONG VARCHAR, the return type is CHAR or LONG VARCHAR. Otherwise, the return type is VARCHAR.
The length and maximum length of the returned value are the same as the length and maximum length of the parameter.
If the CharacterExpression evaluates to null, this function returns null.

    -- returns 'asd1#w'
    VALUES LOWER('aSD1#w')

    SELECT LOWER(flight_id) FROM Flights

LENGTH function
LENGTH is applied to either a character string expression or a bit string expression and returns the number of characters in the result.
Because all built-in data types are implicitly converted to strings, this function can act on all built-in data types.
Syntax

    LENGTH ( { CharacterExpression | BitExpression } )

    -- returns 20
    VALUES LENGTH('supercalifragilistic')
    -- returns 1
    VALUES LENGTH(X'FF')
    -- returns 4
    VALUES LENGTH(1234567890)

LN or LOG function
The LN and LOG functions return the natural logarithm (base e) of the specified number.
The specified number must be a DOUBLE PRECISION number that is greater than zero (0).

• |  | If the specified number is NULL, the result of these functions is NULL.
• |  | If the specified number is zero or a negative number, an exception is returned that indicates that the value is out of range (SQL state 22003).

The data type of the returned value is a DOUBLE PRECISION number.
Syntax

    LN ( number )

    LOG ( number )

LOG10 function
The LOG10 function returns the base-10 logarithm of the specified number.
The specified number must be a DOUBLE PRECISION number that is greater than zero (0).

• |  | If the specified number is NULL, the result of this function is NULL.
• |  | If the specified number is zero or a negative number, an exception is returned that indicates that the value is out of range (SQL state 22003).

The data type of the returned value is a DOUBLE PRECISION number.
Syntax

    LOG10 ( number )

LOCATE function
The LOCATE function is used to search for a string within another string. If the desired string is found, LOCATE returns the index at which it is found. If the desired string is not found, LOCATE returns 0.
Syntax

    LOCATE(CharacterExpression, CharacterExpression [, StartPosition] )

There are two required arguments to the LOCATE function, and a third optional argument.

• |  | The first CharacterExpression specifies the string to search for.
• |  | The second CharacterExpression specifies the string in which to search.
• |  | The third argument is the startPosition, and specifies the position in the second argument at which the search is to start. If the third argument is not provided, the LOCATE function starts its search at the beginning of the second argument.

The return type for LOCATE is an integer. The LOCATE function returns an integer indicating the index position within the second argument at which the first argument was first located. Index positions start with 1. If the first argument is not found in the second argument, LOCATE returns 0. If the first argument is an empty string (''), LOCATE returns the value of the third argument (or 1 if it was not provided), even if the second argument is also an empty string. If a NULL value is passed for either of the CharacterExpression arguments, NULL is returned.

    -- returns 2, since 'love' is found at index position 2:
                VALUES LOCATE('love', 'clover')

    -- returns 0, since 'stove' is not found in 'clover':
                VALUES LOCATE('stove', 'clover')

    -- returns 5 (note the start position is 4):
                VALUES LOCATE('iss', 'Mississippi', 4)

    -- returns 1, because the empty string is a special case:
                VALUES LOCATE('', 'ABC')

    -- returns 0, because 'AAA' is not found in '':
                VALUES LOCATE('AAA', '')

    -- returns 3
                VALUES LOCATE('', '', 3)

LTRIM function
LTRIM removes blanks from the beginning of a character string expression.
Syntax

    LTRIM(CharacterExpression)

A CharacterExpression is a CHAR, VARCHAR, or LONG VARCHAR data type, any built-in type that is implicitly converted to a string.
LTRIM returns NULL if CharacterExpression evaluates to null.

    -- returns 'asdf  '
    VALUES LTRIM(' asdf  ')

MAX function
MAX is an aggregate function that evaluates the maximum of an expression over a set of rows (see Aggregates (set functions)). MAX is allowed only on expressions that evaluate to built-in data types (including CHAR, VARCHAR, DATE, TIME, CHAR FOR BIT DATA, etc.).
Syntax

    MAX ( [ DISTINCT | ALL ] Expression )

The DISTINCT and ALL qualifiers eliminate or retain duplicates, but these qualifiers have no effect in a MAX expression. Only one DISTINCT aggregate expression per SelectExpression is allowed. For example, the following query is not allowed:

    SELECT COUNT (DISTINCT flying_time), MAX (DISTINCT miles)
    FROM Flights

The Expression can contain multiple column references or expressions, but it cannot contain another aggregate or subquery. It must evaluate to a built-in data type. You can therefore call methods that evaluate to built-in data types. (For example, a method that returns a java.lang.Integer or int evaluates to an INTEGER.) If an expression evaluates to NULL, the aggregate skips that value.
The type's comparison rules determine the maximum value. For CHAR and VARCHAR, the number of blank spaces at the end of the value can affect how MAX is evaluated. For example, if the values 'z' and 'z ' are both stored in a column, you cannot control which one will be returned as the maximum, because blank spaces are ignored for character comparisons.
The resulting data type is the same as the expression on which it operates (it will never overflow).

    -- find the latest date in the FlightAvailability table
    SELECT MAX (flight_date) FROM FlightAvailability
    -- find the longest flight originating from each airport,
    -- but only when the longest flight is over 10 hours
    SELECT MAX(flying_time), orig_airport
    FROM Flights
    GROUP BY orig_airport
    HAVING MAX(flying_time) > 10

MIN function
MIN is an aggregate function that evaluates the minimum of an expression over a set of rows (see Aggregates (set functions)). MIN is allowed only on expressions that evaluate to built-in data types (including CHAR, VARCHAR, DATE, TIME, etc.).
Syntax

    MIN ( [ DISTINCT | ALL ] Expression )

The DISTINCT and ALL qualifiers eliminate or retain duplicates, but these qualifiers have no effect in a MIN expression. Only one DISTINCT aggregate expression per SelectExpression is allowed. For example, the following query is not allowed:

    SELECT COUNT (DISTINCT flying_time), MIN (DISTINCT miles)
    FROM Flights

The Expression can contain multiple column references or expressions, but it cannot contain another aggregate or subquery. It must evaluate to a built-in data type. You can therefore call methods that evaluate to built-in data types. (For example, a method that returns a java.lang.Integer or int evaluates to an INTEGER.) If an expression evaluates to NULL, the aggregate skips that value.
The type's comparison rules determine the minimum value. For CHAR and VARCHAR, the number of blank spaces at the end of the value can affect how MIN is evaluated. For example, if the values 'z' and 'z ' are both stored in a column, you cannot control which one will be returned as the minimum, because blank spaces are ignored for character comparisons.
The resulting data type is the same as the expression on which it operates (it will never overflow).

    -- NOT valid:
    SELECT DISTINCT flying_time, MIN(DISTINCT miles) from Flights
    -- valid:
    SELECT COUNT(DISTINCT flying_time), MIN(DISTINCT miles) from Flights
    -- find the earliest date:
    SELECT MIN (flight_date) FROM FlightAvailability;

MINUTE function
The MINUTE function returns the minute part of a value.
The argument must be a time, timestamp, or a valid character string representation of a time or timestamp that is not a CLOB, LONG VARCHAR, or XML value. The result of the function is an integer between 0 and 59. If the argument can be null, the result can be null; if the argument is null, the result is the null value.
Syntax

    MINUTE ( expression )

Example
Select all rows from the "flights" table where the "departure_time" is between 6:00 and 6:30 AM:

    SELECT * FROM flights WHERE HOUR(departure_time) = 6 and MINUTE(departure_time) < 31;

MOD function
MOD returns the remainder (modulus) of argument 1 divided by argument 2. The result is negative only if argument 1 is negative.
Syntax

    mod(integer_type, integer_type)

The result of the function is:

• |  | SMALLINT if both arguments are SMALLINT.
• |  | INTEGER if one argument is INTEGER and the other is INTEGER or SMALLINT.
• |  | BIGINT if one integer is BIGINT and the other argument is BIGINT, INTEGER, or SMALLINT.

The result can be null; if any argument is null, the result is the null value.
MONTH function
The MONTH function returns the month part of a value.
The argument must be a date, timestamp, or a valid character string representation of a date or timestamp that is not a CLOB, LONG VARCHAR, or XML value. The result of the function is an integer between 1 and 12. If the argument can be null, the result can be null; if the argument is null, the result is the null value.
Syntax

    MONTH ( expression )

Example
Select all rows from the EMPLOYEE table for people who were born (BIRTHDATE) in DECEMBER.

    SELECT * FROM EMPLOYEE WHERE MONTH(BIRTHDATE) = 12

NULLIF expressions
Use the NULLIF expressions for conditional expressions in Derby.
NULLIF expression syntax

    NULLIF ( L, R )

The NULLIF expression is very similar to the CASE expression. For example:

    NULLIF(V1,V2)

is equivalent to the following CASE expression:

    CASE WHEN V1=V2 THEN NULL ELSE V1 END

PI function
The PI function returns a value that is closer than any other value to pi.
The constant pi is the ratio of the circumference of a circle to the diameter of a circle.
The data type of the returned value is a DOUBLE PRECISION number.
Syntax

    PI (  )

RADIANS function
The RADIANS function converts a specified number from degrees to radians.
The specified number is an angle measured in degrees, which is converted to an approximately equivalent angle measured in radians. The specified number must be a DOUBLE PRECISION number.
Attention: The conversion from degrees to radians is not exact.
The data type of the returned value is a DOUBLE PRECISION number.
Syntax

    RADIANS ( number )

RTRIM function
RTRIM removes blanks from the end of a character string expression.
Syntax

    RTRIM(CharacterExpression)

A CharacterExpression is a CHAR, VARCHAR, or LONG VARCHAR data type, any built-in type that is implicitly converted to a string.
RTRIM returns NULL if CharacterExpression evaluates to null.

    -- returns ' asdf'
    VALUES RTRIM(' asdf  ')
    -- returns 'asdf'
    VALUES RTRIM('asdf  ')

SECOND function
The SECOND function returns the seconds part of a value.
The argument must be a time, timestamp, or a valid character string representation of a time or timestamp that is not a CLOB, LONG VARCHAR, or XML value. The result of the function is an integer between 0 and 59. If the argument can be null, the result can be null. If the argument is null, the result is 0.
Syntax

    SECOND ( expression )

Example
The RECEIVED column contains a timestamp that has an internal value equivalent to 2005-12-25-17.12.30.000000. To return only the seconds part of the timestamp, use the following syntax:

    SECOND(RECEIVED)

The value 30 is returned.
SESSION_USER function
SESSION_USER returns the authorization identifier or name of the current user. If there is no current user, it returns APP.
USER, CURRENT_USER, and SESSION_USER are synonyms.
Syntax

    SESSION_USER

    VALUES SESSION_USER

SIN function
The SIN function returns the sine of a specified number.
The specified number is the angle, in radians, that you want the sine for. The specified number must be a DOUBLE PRECISION number.

• |  | If the specified number is NULL, the result of this function is NULL.
• |  | If the specified number is zero (0), the result of this function is zero.

The data type of the returned value is a DOUBLE PRECISION number.
Syntax

    SIN ( number )

SMALLINT function
The SMALLINT function returns a small integer representation of a number or character string in the form of a small integer constant.
Syntax

    SMALLINT ( NumericExpression | CharacterExpression )

NumericExpression
An expression that returns a value of any built-in numeric data type. If the argument is a NumericExpression, the result is the same number that would occur if the argument were assigned to a small integer column or variable. If the whole part of the argument is not within the range of small integers, an error occurs. The decimal part of the argument is truncated if present.
CharacterExpression
An expression that returns a character string value of length not greater than the maximum length of a character constant. Leading and trailing blanks are eliminated and the resulting string must conform to the rules for forming an SQL integer constant. However, the value of the constant must be in the range of small integers. The character string cannot be a long string. If the argument is a CharacterExpression, the result is the same number that would occur if the corresponding integer constant were assigned to a small integer column or variable.
The result of the function is a small integer. If the argument can be null, the result can be null. If the argument is null, the result is the null value.
Example
To determine the small integer representation of the number 32767.99, use this clause:

    VALUES SMALLINT (32767.99)

The result is 32767.
To determine the small integer representation of the number 1, use this clause:

    VALUES SMALLINT (1)

The result is 1.
SQRT function
Returns the square root of a floating point number; only the built-in types REAL, FLOAT, and DOUBLE PRECISION are supported. The return type for SQRT is the type of the parameter.
Note: To execute SQRT on other data types, you must cast them to floating point types.
Syntax

    SQRT(FloatingPointExpression)

    -- throws an exception if any row stores a negative number:
    VALUES SQRT(3421E+09)

    -- returns the square root of an INTEGER after casting it as a
    -- floating point data type:
    SELECT SQRT(myDoubleColumn) FROM MyTable

    VALUES SQRT (CAST(25 AS FLOAT));

SUBSTR function
The SUBSTR function acts on a character string expression or a bit string expression. The type of the result is a VARCHAR in the first case and VARCHAR FOR BIT DATA in the second case. The length of the result is the maximum length of the source type.
Syntax

    SUBSTR({ CharacterExpression },
       StartPosition [, LengthOfString ] )

The parameter startPosition and the optional parameter lengthOfString are both integer expressions. The first character or bit has a startPosition of 1. If you specify 0, Derby assumes that you mean 1.
The parameter characterExpression is a CHAR, VARCHAR, or LONG VARCHAR data type or any built-in type that is implicitly converted to a string (except a bit expression).
For character expressions, the startPosition and lengthOfString parameters refer to characters. For bit expressions, the startPosition and lengthOfString parameters refer to bits.
If the startPosition is positive, it refers to position from the start of the source expression (counting the first character as 1). The startPosition cannot be a negative number.
If the lengthOfString is not specified, SUBSTR returns the substring of the expression from the startPosition to the end of the source expression. If lengthOfString is specified, SUBSTR returns a VARCHAR or VARBIT of length lengthOfString starting at the startPosition. The SUBSTR function returns an error if you specify a negative number for the parameter lengthOfString.
Examples
To return a substring of the word hello, starting at the second character and continuing until the end of the word, use the following clause:

    VALUES SUBSTR('hello', 2)

The result is 'ello'.
To return a substring of the word hello, starting at the first character and continuing for two characters, use the following clause:

    VALUES SUBSTR('hello',1,2)

The result is 'he'.
SUM function
SUM is an aggregate function that evaluates the sum of the expression over a set of rows (see Aggregates (set functions)). SUM is allowed only on expressions that evaluate to numeric data types.
Syntax

    SUM ( [ DISTINCT | ALL ] Expression )

The DISTINCT and ALL qualifiers eliminate or retain duplicates. ALL is assumed if neither ALL nor DISTINCT is specified. For example, if a column contains the values 1, 1, 1, 1, and 2, SUM(col) returns a greater value than SUM(DISTINCT col).
Only one DISTINCT aggregate expression per SelectExpression is allowed. For example, the following query is not allowed:

    SELECT AVG (DISTINCT flying_time), SUM (DISTINCT miles)
    FROM Flights

The Expression can contain multiple column references or expressions, but it cannot contain another aggregate or subquery. It must evaluate to a built-in numeric data type. If an expression evaluates to NULL, the aggregate skips that value.
The resulting data type is the same as the expression on which it operates (it might overflow).

    -- find all economy seats available:
    SELECT SUM (economy_seats) FROM Airlines;

    -- use SUM on multiple column references
    -- (find the total number of all seats purchased):
    SELECT SUM (economy_seats_taken + business_seats_taken + firstclass_seats_taken)
    as seats_taken FROM FLIGHTAVAILABILITY;

TAN function
The TAN function returns the tangent of a specified number.
The specified number is the angle, in radians, that you want the tangent for. The specified number must be a DOUBLE PRECISION number.

• |  | If the specified number is NULL, the result of this function is NULL.
• |  | If the specified number is zero (0), the result of this function is zero.

The data type of the returned value is a DOUBLE PRECISION number.
Syntax

    TAN ( number )

TIME function
The TIME function returns a time from a value.
The argument must be a time, timestamp, or a valid string representation of a time or timestamp that is not a CLOB, LONG VARCHAR, or XML value. The result of the function is a time. If the argument can be null, the result can be null; if the argument is null, the result is the null value.
The other rules depend on the data type of the argument specified:

• |  | If the argument is a time: The result is that time.
• |  | If the argument is a timestamp: The result is the time part of the timestamp.
• |  | If the argument is a string: The result is the time represented by the string.

Syntax

    TIME ( expression )

    values time(current_timestamp)

If the current time is 5:03 PM, the value returned is 17:03:00.
TIMESTAMP function
The TIMESTAMP function returns a timestamp from a value or a pair of values.
The rules for the arguments depend on whether the second argument is specified:

• |  | If only one argument is specified: It must be a timestamp, a valid string representation of a timestamp, or a string of length 14 that is not a CLOB, LONG VARCHAR, or XML value. A string of length 14 must be a string of digits that represents a valid date and time in the form yyyyxxddhhmmss, where yyyy is the year, xx is the month, dd is the day, hh is the hour, mm is the minute, and ss is the seconds.
• |  | If both arguments are specified: The first argument must be a date or a valid string representation of a date and the second argument must be a time or a valid string representation of a time.

The other rules depend on whether the second argument is specified:

• |  | If both arguments are specified: The result is a timestamp with the date specified by the first argument and the time specified by the second argument. The microsecond part of the timestamp is zero.
• |  | If only one argument is specified and it is a timestamp: The result is that timestamp.
• |  | If only one argument is specified and it is a string: The result is the timestamp represented by that string. If the argument is a string of length 14, the timestamp has a microsecond part of zero.

Syntax

    TIMESTAMP ( expression [, expression ] )

Examples
The second column in table records_table contains dates (such as 1998-12-25) and the third column contains times of day (such as 17:12:30). You can return the timestamp with this statement:

    SELECT TIMESTAMP(col2, col3) FROM records_table

The following clause returns the value 1998-12-25-17:12:30.0:

    VALUES TIMESTAMP('1998-12-25', '17.12.30');
    1
    --------------------------
    1998-12-25 17:12:30.0

TRIM function
TRIM is a function that takes a character expression and returns that expression with leading and/or trailing pad characters removed. Optional parameters indicate whether leading, or trailing, or both leading and trailing pad characters should be removed, and specify the pad character that is to be removed.
Syntax

    TRIM( [ trimOperands ] trimSource)

    trimOperands  ::= { trimType [ trimCharacter ]  FROM | trimCharacter FROM }
    trimType      ::= { LEADING | TRAILING | BOTH }
    trimCharacter ::= CharacterExpression
    trimSource    ::= CharacterExpression

If trimType is not specified, it will default to BOTH. If trimCharacter is not specified, it will default to the space character (' '). Otherwise the trimCharacter expression must evaulate to one of the following:

• |  | a character string whose length is exactly one, or.
• |  | NULL

If either trimCharacter or trimSource evaluates to NULL, the result of the TRIM function is NULL. Otherwise, the result of the TRIM function is defined as follows:

• |  | If trimType is LEADING, the result will be the trimSource value with all leading occurrences of trimChar removed.
• |  | If trimType is TRAILING, the result will be the trimSource value with all trailing occurrences of trimChar removed.
• |  | If trimType is BOTH, the result will be the trimSource value with all leading *and* trailing occurrences of trimChar removed.

If trimSource's data type is CHAR or VARCHAR, the return type of the TRIM function will be VARCHAR. Otherwise the return type of the TRIM function will be CLOB.
Examples

    -- returns 'derby' (no spaces)
    VALUES TRIM('  derby ')

    -- returns 'derby' (no spaces)
    VALUES TRIM(BOTH ' ' FROM '  derby ')

    -- returns 'derby ' (with a space at the end)
    VALUES TRIM(LEADING ' ' FROM '  derby ')

    -- returns '  derby' (with two spaces at the beginning)
    VALUES TRIM(TRAILING ' ' FROM '  derby ')

    -- returns NULL
    VALUES TRIM(cast (null as char(1)) FROM '  derby ')

    -- returns NULL
    VALUES TRIM(' ' FROM cast(null as varchar(30)))

    -- returns ' derb' (with a space at the beginning)
    VALUES TRIM('y' FROM ' derby')

    -- results in an error because trimCharacter can only be 1 character
    VALUES TRIM('by' FROM ' derby')

UCASE or UPPER function
UCASE or UPPER takes a character expression as a parameter and returns a string in which all alpha characters have been converted to uppercase.
Syntax

    UCASE or UPPER ( CharacterExpression )

If the parameter type is CHAR , the return type is CHAR. Otherwise, the return type is VARCHAR.
Note: UPPER and LOWER follow the database locale. See territory=ll_CC attribute for more information about specifying locale.
The length and maximum length of the returned value are the same as the length and maximum length of the parameter.
Example
To return the string aSD1#w in uppercase, use the following clause:

    VALUES UPPER('aSD1#w')

The value returned is ASD1#W.
USER function
USER returns the authorization identifier or name of the current user. If there is no current user, it returns APP.
USER, CURRENT_USER, and SESSION_USER are synonyms.
Syntax

    USER

    VALUES USER

VARCHAR function
The VARCHAR function returns a varying-length character string representation of a character string.
Character to varchar syntax

    VARCHAR (CharacterStringExpression )

CharacterStringExpression
An expression whose value must be of a character-string data type with a maximum length of 32,672 bytes.
Datetime to varchar syntax

    VARCHAR (DatetimeExpression )

DatetimeExpression
An expression whose value must be of a date, time, or timestamp data type.
Using the EMPLOYEE table, select the job description (JOB defined as CHAR(8)) for Dolores Quintana as a VARCHAR equivelant:

    SELECT VARCHAR(JOB)
    FROM EMPLOYEE
    WHERE LASTNAME = 'QUINTANA'

XMLEXISTS operator
XMLEXISTS is an SQL/XML operator that you can use to query XML values in SQL.
The XMLEXISTS operator has two arguments, an XML query expression and a Derby XML value.
Syntax

    XMLEXISTS ( xquery-string-literal
        PASSING BY REF xml-value-expression [ BY REF ] )

xquery-string-literal
Must be specified as a string literal. If this argument is specified as a parameter, an expression that is not a literal, or a literal that is not a string (for example an integer), Derby throws an error. The xquery-string-literal argument must also be an XPath expression that is supported by Apache Xalan. Derby uses Apache Xalan to evaluate all XML query expressions. Because Xalan does not support full XQuery, neither does Derby. If Xalan is unable to compile or execute the query argument, Derby catches the error that is thrown by Xalan and throws the error as a SQLException. For more on XPath and XQuery expressions, see these Web sites: http://www.w3.org/TR/xpath and http://www.w3.org/TR/xquery/.
xml-value-expression
Must be an XML data value and must constitute a well-formed SQL/XML document. The xml-value-expression argument cannot be a parameter. Derby does not perform implicit parsing nor casting of XML values, so use of strings or any other data type results in an error. If the argument is a sequence that is returned by the Derby XMLQUERY operator, the argument is accepted if it is a sequence of exactly one node that is a document node. Otherwise Derby throws an error.
BY REF
Optional keywords that describe the only value passing mechanism supported by Derby. Since BY REF is also the default passing mechanism, the XMLEXISTS operator behaves the same whether the keywords are present or not. For more information on passing mechanisms, see the SQL/XML specification.
Operator results and combining with other operators
The result of the XMLEXISTS operator is a SQL boolean value that is based on the results from evaluating the xquery-string-literal against the xml-value-expression. The XMLEXISTS operator returns:
UNKNOWN
When the xml-value-expression is null.
TRUE
When the evaluation of the specified query expression against the specified xml-value returns a non-empty sequence of nodes or values.
FALSE
When evaluation of the specified query expression against the specified xml-value returns an empty sequence.
The XMLEXISTS operator does not return the actual results from the evaluation of the query. You must use the XMLQUERY operator to retrieve the actual results.
Since the result of the XMLEXISTS operator is an SQL boolean data type, you can use the XMLEXISTS operator wherever a boolean function is allowed. For example, you can use the XMLEXISTS operator as a check constraint in a table declaration or as a predicate in a WHERE clause.
Examples
In the x_table table, to determine if the xcol XML column for each row has an element called student with an age attribute equal to 20, use this statement:

    SELECT id, XMLEXISTS('//student[@age=20]' PASSING BY REF xcol)
        FROM x_table

In the x_table table, to return the ID for every row whose xcol XML column is non-null and contains the element /roster/student, use this statement:

    SELECT id FROM x_table WHERE XMLEXISTS('/roster/student' PASSING BY REF xcol)

You can create the x_table table with a check constraint that limits which XML values can be inserted into the xcol XML column. In this example, the constraint is that the column has at least one student element with an age attribute with a value that is less than 25. To create the table, use this statement:

    CREATE TABLE x_table ( id INT, xcol XML CHECK (XMLEXISTS ('//student[@age < 25]' PASSING BY REF xcol)) )

Usage note
Derby requires that a JAXP parser, such as Apache Xerces, and that Apache Xalan are listed in the Java classpath for the XML functions to work. If either the JAXP parser or Xalan is missing from the classpath, attempts to use the XMLEXISTS operator will result in an error.
XMLPARSE operator
XMLPARSE is a SQL/XML operator that you use to parse a character string expression into a Derby XML value.
You can use the result of this operator temporarily or you can store the result permanently in Derby XML columns. Whether temporary or permanent, you can use the XML value as an input to the other Derby XML operators, such as XMLEXISTS and XMLQUERY.
Syntax

    XMLPARSE (DOCUMENT string-value-expression PRESERVE WHITESPACE)

DOCUMENT
Required keyword that describes the type of XML input that Derby can parse. Derby can only parse string expressions that constitute well-formed XML documents. This is because Derby uses a JAXP parser to parse all string values. The JAXP parser expects the string-value-expression to constitute a well-formed XML document. If the string does not constitute a well-formed document, JAXP throws an error. Derby catches the error and throws the error as a SQLException.
string-value-expression
Any expression that evaluates to a SQL character type, such as CHAR, VARCHAR, LONG VARCHAR, or CLOB. The string-value-expression argument can also be a parameter. You must use the CAST function when you specify the parameter to indicate the type of value that is bound into the parameter. Derby must verify that the parameter is the correct data type before the value is parsed as an XML document. If a parameter is specified without the CAST function, or if the CAST is to a non-character datatype, Derby throws an error.
PRESERVE WHITESPACE
Required keywords that describe how Derby handles whitespace between consecutive XML nodes. When the PRESERVE WHITESPACE keywords are used, Derby preserves whitespace as dictated by the SQL/XML rules for preserving whitespace.
For more information on what constitutes a well-formed XML document, see the following specification: http://www.w3.org/TR/REC-xml/#sec-well-formed .
Restriction: The SQL/XML standard dictates that the argument to the XMLPARSE operator can also be a binary string. However, Derby only supports character string input for the XMLPARSE operator.
Examples
To insert a simple XML document into the xcol XML column in the x_table table, use the following statement:

    INSERT INTO x_table VALUES
        (1,
        XMLPARSE(DOCUMENT '
            <roster>
              <student age="18">AB</student>
              <student age="23">BC</student>
              <student>NOAGE</student>
            </roster>'
          PRESERVE WHITESPACE)
        )

To insert a large XML document into the xcol XML column in the x_table table, from JDBC use the following statement:

    INSERT INTO x_table VALUES
        (2,
        XMLPARSE (DOCUMENT CAST (? AS CLOB) PRESERVE WHITESPACE)
        )

You should bind into the statement using the setCharacterStream() method, or any other JDBC setXXX method that works for the CAST target type.
Usage note
Derby requires that a JAXP parser, such as Apache Xerces, and that Apache Xalan are listed in the Java classpath for the XML functions to work. If either the JAXP parser or Xalan is missing from the classpath, attempts to use the XMLPARSE operator will result in an error.
XMLQUERY operator
XMLQUERY is a SQL/XML operator that you can use to query XML values in SQL.
The XMLQUERY operator has two arguments, an XML query expression and a Derby XML value.
Syntax

    XMLQUERY ( xquery-string-literal
        PASSING BY REF xml-value-expression
        [ RETURNING SEQUENCE [ BY REF ] ]
        EMPTY ON EMPTY
        )

xquery-string-literal
Must be specified as a string literal. If this argument is specified as a parameter, an expression that is not a literal, or a literal that is not a string (for example an integer),Derby throws an error. The xquery-string-literal argument must also be an XPath expression that is supported by Apache Xalan. Derby uses Apache Xalan to evaluate all XML query expressions. Because Xalan does not support full XQuery, neither does Derby. If Xalan is unable to compile or execute the query argument, Derby catches the error that is thrown by Xalan and throws the error as a SQLException. For more on XPath and XQuery expressions, see these Web sites: http://www.w3.org/TR/xpath and http://www.w3.org/TR/xquery/.
xml-value-expression
Must be an XML data value and must constitute a well-formed SQL/XML document. The xml-value-expression argument cannot be a parameter. Derby does not perform implicit parsing nor casting of XML values, so use of strings or any other data type results in an error. If the argument is a sequence that is returned by a Derby XMLQUERY operation, the argument is accepted if it is a sequence of exactly one node that is a document node. Otherwise Derby throws an error.
BY REF
Optional keywords that describe the only value passing mechanism supported by Derby. Since BY REF is also the default passing mechanism, the XMLQUERY operator behaves the same whether the keywords are present or not. For more information on passing mechanisms, see the SQL/XML specification.
RETURNING SEQUENCE
Optional keywords that describe the only XML type returned by the Derby XMLQUERY operator. Since SEQUENCE is also the default return type, the XMLQUERY operator behaves the same whether the keywords are present or not. For more information on the different XML return types, see the SQL/XML specification.
EMPTY ON EMPTY
Required keywords that describe the way in which XMLQUERY handles an empty result sequence. The XMLQUERY operator returns an empty sequence exactly as the sequence is. The XMLQUERY operator does not convert the empty sequence to a null value. When an empty result sequence is serialized, the result is an empty string. Derby does not consider an empty result sequence to be a well-formed XML document.
The result of the XMLQUERY operator is a value of type XML. The result represents a sequence of XML nodes or values. Atomic values, such as strings, can be part of the result sequence. The result of an XMLQUERY operator is not guaranteed to represent a well-formed XML document and it might not be possible to insert the result of an XMLQUERY operator into an XML column. To store the result in an XML column, the result must be a sequence with exactly one item in the sequence and the item must be a well-formed document node. The result can be viewed only in serialized form by explicitly using the XMLSERIALIZE operator.
Examples
In the x_table table, to search the XML column xcol and return the students that have an age attribute that is greater than 20, use the following statement:

    SELECT ID,
        XMLSERIALIZE(
            XMLQUERY('//student[@age>20]' PASSING BY REF xcol EMPTY ON EMPTY)
        AS VARCHAR(50))
    FROM x_table

The result set for this query contains a row for every row in x_table, regardless of whether or not the XMLQUERY operator actually returns results.
In the x_table table, to search the XML column xcol and return the ages for any students named BC, use the following statement:

    SELECT ID,
        XMLSERIALIZE(
            XMLQUERY('string(//student[text() = "BC"]/@age)' PASSING BY REF xcol EMPTY ON EMPTY)
        AS VARCHAR(50))
    FROM x_table
    WHERE
        XMLEXISTS('//student[text() = "BC"]' PASSING BY REF xcol)

The result set for this query contains a row for only the rows in x_table that have a student whose name is BC.
Usage note
Derby requires that a JAXP parser, such as Apache Xerces, and that Apache Xalan are listed in the Java classpath for the XML functions to work. If either the JAXP parser or Xalan is missing from the classpath, attempts to use the XMLQUERY operator will result in an error.
XMLSERIALIZE operator
XMLSERIALIZE is a SQL/XML operator that you can use to convert an XML type to a character type. There is no other way to convert the type of a Derby XML value.
Attention: Serialization is performed based on the SQL/XML serialization rules. These rules, combined with the fact that Derby supports only a subset of the XMLSERIALIZE syntax, dictate that the results of an XMLSERIALIZE operation are not guaranteed to be in-tact copies of the original XML text. For example, assume that [xString] is a textual representation of a well-formed XML document. You issue the following statements:

    INSERT INTO x_table (id, xcol)
        VALUES (3, XMLPARSE(DOCUMENT '[xString]' PRESERVE WHITESPACE));

    SELECT id, XMLSERIALIZE(xcol AS VARCHAR(100))
        FROM x_table WHERE id = 3;

There is no guarantee that the result of the XMLSERIALIZE operator will be identical to the original [xString] representation. Certain transformations can occur as part of XMLSERIALIZE processing, and those transformations are defined in the SQL/XML specification. In some cases the result of XMLSERIALIZE might actually be the same as the original textual representation, but that is not guaranteed.
When an XMLSERIALIZE operator is specified as part of the top-level result set for a query, the result can be accessed from JDBC by using whatever JDBC getXXX methods are allowed on the string-data-type argument that is included in the XMLSERIALIZE syntax. If you attempt to select the contents of an XML value from a top-level result set without using the XMLSERIALIZE operator, Derby throws an error. Derby does not implicitly serialize XML values.
Syntax

    XMLSERIALIZE ( xml-value-expression AS string-data-type )

xml-value-expression
Can be any Derby XML value, including an XML result sequence generated by the XMLQUERY operator. The xml-value-expression argument cannot be a parameter.
string-data-type
Must be a SQL character string type, such as CHAR, VARCHAR, LONG VARCHAR, or CLOB. If you specify a type that is not a valid character string type, Derby throws an error.
Examples
In the x_table table, to display the contents of the xcol XML column, use this statement:

    SELECT ID,
        XMLSERIALIZE(
        xcol AS CLOB)
    FROM x_table

To retrieve the results from JDBC, you can use the JDBC getCharacterStream() or getString() method.
To display the results of an XMLQUERY operation, use the following statement:

    SELECT ID,
        XMLSERIALIZE(
            XMLQUERY('//student[@age>20]'
               PASSING BY REF xcol EMPTY ON EMPTY)
        AS VARCHAR(50))
    FROM x_table

Usage note
Derby requires that a JAXP parser, such as Apache Xerces, and that Apache Xalan are listed in the Java classpath for the XML functions to work. If either the JAXP parser or Xalan is missing from the classpath, attempts to use the XMLSERIALIZE operator will result in an error
YEAR function
The YEAR function returns the year part of a value. The argument must be a date, timestamp, or a valid character string representation of a date or timestamp. The result of the function is an integer between 1 and 9 999. If the argument can be null, the result can be null; if the argument is null, the result is the null value.
Syntax

    YEAR ( expression )

Example
Select all the projects in the PROJECT table that are scheduled to start (PRSTDATE) and end (PRENDATE) in the same calendar year.

    SELECT * FROM PROJECT WHERE YEAR(PRSTDATE) = YEAR(PRENDATE)

Built-in system functions
This section describes the different built-in system functions available with Derby.
SYSCS_UTIL.SYSCS_CHECK_TABLE system function
The SYSCS_UTIL.SYSCS_CHECK_TABLE function checks the specified table, ensuring that all of its indexes are consistent with the base table. If the table and indexes are consistent, the method returns a SMALLINT with value 1. If the table and indexes are inconsistent, the function will throw an exception.
Syntax

    SMALLINT SYSCS_UTIL.SYSCS_CHECK_TABLE(IN SCHEMANAME VARCHAR(128),
    IN TABLENAME VARCHAR(128))

An error will occur if either SCHEMANAME or TABLENAME are null.
Example

    VALUES SYSCS_UTIL.SYSCS_CHECK_TABLE('SALES', 'ORDERS');

SYSCS_UTIL.SYSCS_GET_DATABASE_PROPERTY system function
The SYSCS_UTIL.SYSCS_GET_DATABASE_PROPERTY function fetches the value of a property specified by KEY of the database on the current connection.
Syntax

    VARCHAR(32762) SYSCS_UTIL.SYSCS_GET_DATABASE_PROPERTY(IN KEY VARCHAR(128))

An error will be returned if KEY is null.
Example

    VALUES SYSCS_UTIL.SYSCS_GET_DATABASE_PROPERTY('key_value_string');

SYSCS_UTIL.SYSCS_GET_RUNTIMESTATISTICS system function
The SYSCS_UTIL.SYSCS_GET_RUNTIMESTATISTICS function returns a VARCHAR(32762) value representing the query execution plan and run time statistics for a java.sql.ResultSet. A query execution plan is a tree of execution nodes. There are a number of possible node types. Statistics are accumulated during execution at each node. The types of statistics include the amount of time spent in specific operations, the number of rows passed to the node by its children, and the number of rows returned by the node to its parent. (The exact statistics are specific to each node type.) SYSCS_UTIL.SYSCS_GET_RUNTIMESTATISTICS is most meaningful for DML statements such as SELECT, INSERT, DELETE and UPDATE.
Syntax

    VARCHAR(32762) SYSCS_UTIL.SYSCS_GET_RUNTIMESTATISTICS()

Example

    VALUES SYSCS_UTIL.SYSCS_GET_RUNTIMESTATISTICS()

Built-in system procedures
Some built-in procedures are not compatible with SQL syntax used by other relational databases. These procedures can only be used with Derby.
SYSCS_UTIL.SYSCS_BACKUP_DATABASE system procedure
The SYSCS_UTIL.SYSCS_BACKUP_DATABASE system procedure backs up the database to a specified backup directory.
Syntax

    SYSCS_UTIL.SYSCS_BACKUP_DATABASE(IN BACKUPDIR VARCHAR())

No result is returned from the procedure.
BACKUPDIR
An input argument of type VARCHAR(32672) that specifies the path to a directory, where the backup should be stored. Relative paths are resolved based on the current user directory, user.dir, of the JVM where the database backup is occurring. Relative paths are not resolved based on the derby home directory. To avoid confusion, use the absolute path.
JDBC example
The following example backs up the database to the c:/backupdir directory:

    CallableStatement cs = conn.prepareCall
    ("CALL SYSCS_UTIL.SYSCS_BACKUP_DATABASE(?)");
    cs.setString(1, "c:/backupdir");
    cs.execute();
    cs.close();

SQL example
The following example backs up the database to the c:/backupdir directory:

    CALL SYSCS_UTIL.SYSCS_BACKUP_DATABASE('c:/backupdir');

SYSCS_UTIL.SYSCS_BACKUP_DATABASE_NOWAIT system procedure
The SYSCS_UTIL.SYSCS_BACKUP_DATABASE_NOWAIT system procedure backs up the database to a specified backup directory.
If there are any transactions in progress with unlogged operations at the start of the backup, the SYSCS_UTIL.SYSCS_BACKUP_DATABASE_NOWAIT system procedure returns an error immediately, instead of waiting for those transactions to complete.
Syntax

    SYSCS_UTIL.SYSCS_BACKUP_DATABASE_NOWAIT(IN BACKUPDIR VARCHAR())

No result is returned from the procedure.
BACKUPDIR
An input argument of type VARCHAR(32672) that specifies the path to a directory, where the backup should be stored. Relative paths are resolved based on the current user directory, user.dir, of the JVM where the database backup is occurring. Relative paths are not resolved based on the derby home directory. To avoid confusion, use the absolute path.
JDBC example
The following example backs up the database to the c:/backupdir directory:

    CallableStatement cs = conn.prepareCall
    ("CALL SYSCS_UTIL.SYSCS_BACKUP_DATABASE_NOWAIT(?)");
    cs.setString(1, "c:/backupdir");
    cs.execute();
    cs.close();

SQL example
The following example backs up the database to the c:/backupdir directory:

    CALL SYSCS_UTIL.SYSCS_BACKUP_DATABASE_NOWAIT('c:/backupdir');

SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE system procedure
The SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE system procedure backs up the database to a specified backup directory and enables the database for log archive mode.
Syntax

    SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE
    (IN BACKUPDIR VARCHAR(32672), IN SMALLINT DELETE_ARCHIVED_LOG_FILES)

No result is returned from the procedure.
BACKUPDIR
An input argument of type VARCHAR(32672) that specifies the path to a directory, where the backup should be stored. Relative paths are resolved based on the current user directory, user.dir, of the JVM where the database backup is occurring. Relative paths are not resolved based on the derby home directory. To avoid confusion, use the absolute path
DELETE_ARCHIVED_LOG_FILES
If the input parameter value for the DELETE_ARCHIVED_LOG_FILES parameter is a non-zero value, online archived log files that were created before this backup will be deleted. The log files are deleted only after a successful backup.
JDBC example
The following example backs up the database to the c:/backupdir directory:

    CallableStatement cs = conn.prepareCall
    ("CALL SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE(?, ?)");
    cs.setString(1, "c:/backupdir");
    cs.setInt(2, 0);
    cs.execute();

SQL examples
The following example backs up the database to the c:/backupdir directory, enables log archive mode, and does not delete any existing online archived log files:

    SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE('c:/backupdir', 0)

The following example backs up the database to the c:/backupdir directory and, if this backup is successful, deletes existing online archived log files:

    SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE('c:/backupdir', 1)

SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE_NOWAIT system procedure
The SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE_NOWAIT system procedure backs up the database to a specified backup directory and enables the database for log archive mode. This procedure returns an error if there are any transactions in progress that have unlogged operations at the start of the backup, instead of waiting for those transactions to complete.
Syntax

    SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE_NOWAIT
    (IN BACKUPDIR VARCHAR(32672),
    IN SMALLINT DELETE_ARCHIVED_LOG_FILES)

No result is returned from the procedure.
BACKUPDIR
An input argument of type VARCHAR(32672) that specifies the path to a directory, where the backup should be stored. Relative paths are resolved based on the current user directory, user.dir, of the JVM where the database backup is occurring. Relative paths are not resolved based on the derby home directory. To avoid confusion, use the absolute path.
DELETE_ARCHIVED_LOG_FILES
If the input parameter value for the DELETE_ARCHIVED_LOG_FILES parameter is a non-zero value, online archived log files that were created before this backup will be deleted. The log files are deleted only after a successful backup.
JDBC example
The following example backs up the database to the c:/backupdir directory and enables log archive mode:

    CallableStatement cs = conn.prepareCall
    ("CALL SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE_NOWAIT(?, ?)");
    cs.setString(1, "c:/backupdir");
    cs.setInt(2, 0);
    cs.execute();

SQL examples
The following example backs up the database to the c:/backupdir directory, enables log archive mode, and does not delete any existing online archived log files:

    SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE_NOWAIT('c:/backupdir', 0)

The following example backs up the database to the c:/backupdir directory and, if this backup is successful, deletes existing online archived log files:

    SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE_NOWAIT('c:/backupdir', 1)

SYSCS_UTIL.SYSCS_CHECKPOINT_DATABASE system procedure
The SYSCS_UTIL.SYSCS_CHECKPOINT_DATABASE system procedure checkpoints the database by flushing all cached data to disk.
Syntax

    SYSCS_UTIL.SYSCS_CHECKPOINT_DATABASE()

No result is returned by this procedure.
JDBC example

    CallableStatement cs = conn.prepareCall
    ("CALL SYSCS_UTIL.SYSCS_CHECKPOINT_DATABASE()");
    cs.execute();
    cs.close();

SQL Example

    CALL SYSCS_UTIL.SYSCS_CHECKPOINT_DATABASE();

SYSCS_UTIL.SYSCS_COMPRESS_TABLE system procedure
Use the SYSCS_UTIL.SYSCS_COMPRESS_TABLE system procedure to reclaim unused, allocated space in a table and its indexes. Typically, unused allocated space exists when a large amount of data is deleted from a table, or indexes are updated. By default, Derby does not return unused space to the operating system. For example, once a page has been allocated to a table or index, it is not automatically returned to the operating system until the table or index is destroyed. SYSCS_UTIL.SYSCS_COMPRESS_TABLE allows you to return unused space to the operating system.
The SYSCS_UTIL.SYSCS_COMPRESS_TABLE system procedure updates statistics on all indexes as part of the index rebuilding process.
Syntax

    SYSCS_UTIL.SYSCS_COMPRESS_TABLE (IN SCHEMANAME VARCHAR(128),
    IN TABLENAME VARCHAR(128), IN SEQUENTIAL SMALLINT)

SCHEMANAME
An input argument of type VARCHAR(128) that specifies the schema of the table. Passing a null will result in an error.
TABLENAME
An input argument of type VARCHAR(128) that specifies the table name of the table. The string must exactly match the case of the table name, and the argument of "Fred" will be passed to SQL as the delimited identifier 'Fred'. Passing a null will result in an error.
SEQUENTIAL
A non-zero input argument of type SMALLINT will force the operation to run in sequential mode, while an argument of 0 will force the operation not to run in sequential mode. Passing a null will result in an error.
SQL example
To compress a table called CUSTOMER in a schema called US, using the SEQUENTIAL option:

    call SYSCS_UTIL.SYSCS_COMPRESS_TABLE('US', 'CUSTOMER', 1)

Java example
To compress a table called CUSTOMER in a schema called US, using the SEQUENTIAL option:

    CallableStatement cs = conn.prepareCall
    ("CALL SYSCS_UTIL.SYSCS_COMPRESS_TABLE(?, ?, ?)");
    cs.setString(1, "US");
    cs.setString(2, "CUSTOMER");
    cs.setShort(3, (short) 1);
    cs.execute();

If the SEQUENTIAL parameter is not specified, Derby rebuilds all indexes concurrently with the base table. If you do not specify the SEQUENTIAL argument, this procedure can be memory-intensive and use a lot of temporary disk space (an amount equal to approximately two times the used space plus the unused, allocated space). This is because Derby compresses the table by copying active rows to newly allocated space (as opposed to shuffling and truncating the existing space). The extra space used is returned to the operating system on COMMIT.
When SEQUENTIAL is specified, Derby compresses the base table and then compresses each index sequentially. Using SEQUENTIAL uses less memory and disk space, but is more time-intensive. Use the SEQUENTIAL argument to reduce memory and disk space usage.
SYSCS_UTIL.SYSCS_COMPRESS_TABLE cannot release any permanent disk space back to the operating system until a COMMIT is issued. This means that the space occupied by both the base table and its indexes cannot be released. Only the disk space that is temporarily claimed by an external sort can be returned to the operating system prior to a COMMIT.
Tip: We recommend that you issue the SYSCS_UTIL.SYSCS_COMPRESS_TABLE system procedure in the auto-commit mode.
Note: This procedure acquires an exclusive table lock on the table being compressed. All statement plans dependent on the table or its indexes are invalidated. For information on identifying unused space, see the Java DB Server and Administration Guide.
SYSCS_UTIL.SYSCS_INPLACE_COMPRESS_TABLE system procedure
Use the SYSCS_UTIL.SYSCS_INPLACE_COMPRESS_TABLE system procedure to reclaim unused, allocated space in a table and its indexes. Typically, unused allocated space exists when a large amount of data is deleted from a table and there has not been any subsequent inserts to use the space created by the deletes. By default, Derby does not return unused space to the operating system. For example, once a page has been allocated to a table or index, it is not automatically returned to the operating system until the table or index is destroyed. SYSCS_UTIL.SYSCS_INPLACE_COMPRESS_TABLE allows you to return unused space to the operating system.
This system procedure can be used to force three levels of in-place compression of a SQL table: PURGE_ROWS, DEFRAGMENT_ROWS, and TRUNCATE_END. Unlike SYSCS_UTIL.SYSCS_COMPRESS_TABLE(), all work is done in place in the existing table/index.
Syntax

    SYSCS_UTIL.SYSCS_INPLACE_COMPRESS_TABLE(
    		IN SCHEMANAME VARCHAR(128),
    		IN TABLENAME VARCHAR(128),
    		IN PURGE_ROWS SMALLINT,
    		IN DEFRAGMENT_ROWS SMALLINT,
    		IN TRUNCATE_END SMALLINT )

SCHEMANAME
An input argument of type VARCHAR(128) that specifies the schema of the table. Passing a null will result in an error.
TABLENAME
An input argument of type VARCHAR(128) that specifies the table name of the table. The string must exactly match the case of the table name, and the argument of "Fred" will be passed to SQL as the delimited identifier 'Fred'. Passing a null will result in an error.
PURGE_ROWS
If PURGE_ROWS is set to a non-zero value, then a single pass is made through the table which will purge committed deleted rows from the table. This space is then available for future inserted rows, but remains allocated to the table. As this option scans every page of the table, its performance is linearly related to the size of the table.
DEFRAGMENT_ROWS
If DEFRAGMENT_ROWS is set to a non-zero value, then a single defragment pass is made which will move existing rows from the end of the table towards the front of the table. The goal of defragmentation is to empty a set of pages at the end of the table which can then be returned to the operating system by the TRUNCATE_END option. It is recommended to only run DEFRAGMENT_ROWS if also specifying the TRUNCATE_END option. The DEFRAGMENT_ROWS option scans the whole table and needs to update index entries for every base table row move, so the execution time is linearly related to the size of the table.
TRUNCATE_END
If TRUNCATE_END is set to a non-zero value, then all contiguous pages at the end of the table will be returned to the operating system. Running the PURGE_ROWS and/or DEFRAGMENT_ROWS options may increase the number of pages affected. This option by itself performs no scans of the table.
SQL example
To compress a table called CUSTOMER in a schema called US, using all available compress options:

    call SYSCS_UTIL.SYSCS_INPLACE_COMPRESS_TABLE('US', 'CUSTOMER', 1, 1, 1);

To return the empty free space at the end of the same table, the following call will run much quicker than running all options but will likely return much less space:

    call SYSCS_UTIL.SYSCS_INPLACE_COMPRESS_TABLE('US', 'CUSTOMER', 0, 0, 1);

Java example
To compress a table called CUSTOMER in a schema called US, using all available compress options:

    CallableStatement cs = conn.prepareCall
    ("CALL SYSCS_UTIL.SYSCS_INPLACE_COMPRESS_TABLE(?, ?, ?, ?, ?)");
    cs.setString(1, "US");
    cs.setString(2, "CUSTOMER");
    cs.setShort(3, (short) 1);
    cs.setShort(4, (short) 1);
    cs.setShort(5, (short) 1);
    cs.execute();

To return the empty free space at the end of the same table, the following call will run much quicker than running all options but will likely return much less space:

    CallableStatement cs = conn.prepareCall
    ("CALL SYSCS_UTIL.SYSCS_INPLACE_COMPRESS_TABLE(?, ?, ?, ?, ?)");
    cs.setString(1, "US");
    cs.setString(2, "CUSTOMER");
    cs.setShort(3, (short) 0);
    cs.setShort(4, (short) 0);
    cs.setShort(5, (short) 1);
    cs.execute();

Tip: We recommend that you issue the SYSCS_UTIL.SYSCS_INPLACE_COMPRESS_TABLE system procedure in the auto-commit mode.
Note: This procedure acquires an exclusive table lock on the table being compressed. All statement plans dependent on the table or its indexes are invalidated. For information on identifying unused space, see the Java DB Server and Administration Guide.
SYSCS_UTIL.SYSCS_DISABLE_LOG_ARCHIVE_MODE system procedure
The SYSCS_UTIL.SYSCS_DISABLE_LOG_ARCHIVE_MODE system procedure disables the log archive mode and deletes any existing online archived log files if the DELETE_ARCHIVED_LOG_FILES input parameter is non-zero.
Syntax

    SYSCS_UTIL.SYSCS_DISABLE_LOG_ARCHIVE_MODE(IN SMALLINT DELETE_ARCHIVED_LOG_FILES)

No result is returned from the procedure.
DELETE_ARCHIVED_LOG_FILES
If the input parameter value for the DELETE_ARCHIVED_LOG_FILES parameter is a non-zero value, then all existing online archived log files are deleted. If the parameter value is zero, then exiting online archived log files are not deleted.
JDBC example
The following example disables log archive mode for the database and deletes any existing log archive files.

    CallableStatement cs = conn.prepareCall
    ("CALL SYSCS_UTIL.SYSCS_DISABLE_LOG_ARCHIVE_MODE(?)");
    cs.setInt(1, 1);
    cs.execute();
    cs.close();

SQL examples
The following example disables log archive mode for the database and retains any existing log archive files:

    CALL SYSCS_UTIL.SYSCS_DISABLE_LOG_ARCHIVE_MODE DELETE_ARCHIVED_LOG_FILES(0);

The following example disables log archive mode for the database and deletes any existing log archive files:

    CALL SYSCS_UTIL.SYSCS_DISABLE_LOG_ARCHIVE_MODE DELETE_ARCHIVED_LOG_FILES(1);

SYSCS_UTIL.SYSCS_EXPORT_TABLE system procedure
The SYSCS_UTIL.SYSCS_EXPORT_TABLE system procedure exports all of the data from a table to an operating system file in a delimited data file format.
Syntax

    SYSCS_UTIL.SYSCS_EXPORT_TABLE (IN SCHEMANAME  VARCHAR(128),
    IN TABLENAME VARCHAR(128), IN FILENAME VARCHAR(32672),
    IN COLUMNDELIMITER CHAR(1), IN CHARACTERDELIMITER CHAR(1),
    IN CODESET VARCHAR(128))

No result is returned from the procedure.
SCHEMANAME
An input argument of type VARCHAR(128) that specifies the schema name of the table. Passing a NULL value will use the default schema name.
TABLENAME
An input argument of type VARCHAR(128) that specifies the name of the table/view from which the data is to be exported. Passing a null will result in an error.
FILENAME
An input argument of type VARCHAR(32672) that specifies the name of the file to which data is to be exported. If the complete path to the file is not specified, the export procedure uses the current directory and the default drive as the destination. If the name of a file that already exists is specified, the export procedure overwrites the contents of the file; it does not append the information. Passing a null will result in an error.
COLUMNDELIMITER
An input argument of type CHAR(1) that specifies a column delimiter. The specified character is used in place of a comma to signal the end of a column. Passing a NULL value will use the default value; the default value is a comma (,).
CHARACTERDELIMITER
An input argument of type CHAR(1) that specifies a character delimiter. The specified character is used in place of double quotation marks to enclose a character string. Passing a NULL value will use the default value; the default value is a double quotation mark (").
CODESET
An input argument of type VARCHAR(128) that specifies the code set of the data in the exported file. The name of the code set should be one of the Java-supported character encodings. Data is converted from the database code set to the specified code set before writing to the file. Passing a NULL value will write the data in the same code set as the JVM in which it is being executed.
If you create a schema or table name as a non-delimited identifier, you must pass the name to the export procedure using all uppercase characters. If you created a schema, table, or column name as a delimited identifier, you must pass the name to the export procedure using the same case that was used when it was created.
Usage
For additional information on using this procedure see the section "Using the bulk import and export procedures" in the Java DB Tools and Utilities Guide.
Example
The following example shows how to export information from the STAFF table in a SAMPLE database to the myfile.del file.

    CALL SYSCS_UTIL.SYSCS_EXPORT_TABLE (null, 'STAFF', 'myfile.del', null, null, null);

SYSCS_UTIL.SYSCS_EXPORT_TABLE_LOBS_TO_EXTFILE system procedure
Use the SYSCS_UTIL.SYSCS_EXPORT_TABLE_LOBS_TO_EXTFILE system procedure to export all the data from a table, and place the LOB data into a separate export file. A reference to the location of the LOB data is placed in the LOB column in the main export file.
Syntax

    SYSCS_UTIL.SYSCS_EXPORT_TABLE_LOBS_TO_EXTFILE (
        IN SCHEMANAME VARCHAR(128),
        IN TABLENAME VARCHAR(128),
        IN FILENAME VARCHAR(32672),
        IN COLUMNDELIMITER CHAR(1),
        IN CHARACTERDELIMITER CHAR(1),
        IN CODESET VARCHAR(128)
        IN LOBSFILENAME VARCHAR(32672)
        )

When you run this procedure, the column data is written to the main export file in a delimited data file format.
SCHEMANAME
Specifies the schema of the table. You can specify a NULL value to use the default schema name. The SCHEMANAME parameter takes an input argument that is a VARCHAR (128) data type.
TABLENAME
Specifies the table name of the table or view from which the data is to be exported. This table cannot be a system table or a declared temporary table. The string must exactly match the case of the table name. Specifying a NULL value results in an error. The TABLENAME parameter takes an input argument that is a VARCHAR (128) data type.
FILENAME
Specifies the file to which the data is to be exported. If the path is omitted, the current working directory is used. If the name of a file that already exists is specified, the export utility overwrites the contents of the file; it does not append the information. The specified location of the file should refer to the server-side location if you are using the Network Server. Specifying a NULL value results in an error. The FILENAME parameter takes an input argument that is a VARCHAR (32672) data type.
COLUMNDELIMITER
Specifies a column delimiter. The specified character is used in place of a comma to signify the end of a column. You can specify a NULL value to use the default value of a comma. The COLUMNDELIMITER parameter must be a CHAR (1) data type.
CHARACTERDELIMITER
Specifies a character delimiter. The specified character is used in place of double quotation marks to enclose a character string. You can specify a NULL value to use the default value of a double quotation mark. The CHARACTERDELIMITER parameter takes an input argument that is a CHAR (1) data type.
CODESET
Specifies the code set of the data in the export file. The code set name should be one of the Java-supported character encoding sets. Data is converted from the database code page to the specified code page before writing to the file. You can specify a NULL value to write the data in the same code page as the JVM in which it is being executed. The CODESET parameter takes an input argument that is a VARCHAR (128) data type.
LOBSFILENAME
Specifies the file that the large object data is exported to. If the path is omitted, the lob file is created in the same directory as the main export file. If you specify the name of an existing file, the export utility overwrites the contents of the file. The data is not appended to the file. If you are using the Network Server, the file should be in a server-side location. Specifying a NULL value results in an error. The LOBSFILENAME parameter takes an input argument that is a VARCHAR (32672) data type.
If you create a schema, table, or column name as a non-delimited identifier, you must pass the name to the export procedure using all uppercase characters. If you created a schema or table name as a delimited identifier, you must pass the name to the export procedure using the same case that was used when it was created.
Usage
For additional information on using this procedure see the section "Using the bulk import and export procedures" in the Java DB Tools and Utilities Guide.
Example exporting all data from a table, using a separate export file for the LOB data
The following example shows how to export data from the STAFF table in a sample database to the main file staff.del and the LOB export file pictures.dat.

    CALL SYSCS_UTIL.SYSCS_EXPORT_TABLE_LOBS_TO_EXTFILE(
        'APP', 'STAFF', 'c:\data\staff.del', ',' ,'"',
        'UTF-8', 'c:\data\pictures.dat');

SYSCS_UTIL.SYSCS_EXPORT_QUERY system procedure
The SYSCS_UTIL.SYSCS_EXPORT_QUERY system procedure exports the results of a SELECT statement to an operating system file in a delimited data file format.
Syntax

    SYSCS_UTIL.SYSCS_EXPORT_QUERY(IN SELECTSTATEMENT VARCHAR(32672),
    IN FILENAME VARCHAR(32672), IN COLUMNDELIMITER CHAR(1),
    IN CHARACTERDELIMITER CHAR(1), IN CODESET VARCHAR(128))

No result is returned from the procedure.
SELECTSTATEMENT
An input argument of type VARCHAR(32672) that specifies the select statement (query) that will return the data to be exported. Passing a NULL value will result in an error.
FILENAME
An input argument of type VARCHAR(32672) that specifies the name of the file to which data is to be exported. If the complete path to the file is not specified, the export procedure uses the current directory and the default drive as the destination. If the name of a file that already exists is specified, the export procedure overwrites the contents of the file; it does not append the information. Passing a null will result in an error.
COLUMNDELIMITER
An input argument of type CHAR(1) that specifies a column delimiter. The specified character is used in place of a comma to signal the end of a column. Passing a NULL value will use the default value; the default value is a comma (,).
CHARACTERDELIMITER
An input argument of type CHAR(1) that specifies a character delimiter. The specified character is used in place of double quotation marks to enclose a character string. Passing a NULL value will use the default value; the default value is a double quotation mark (").
CODESET
An input argument of type VARCHAR(128) that specifies the code set of the data in the exported file. The name of the code set should be one of the Java-supported character encodings. Data is converted from the database code set to the specified code set before writing to the file. Passing a NULL value will write the data in the same code set as the JVM in which it is being executed.
Usage
For additional information on using this procedure see the section "Using the bulk import and export procedures" in the Java DB Tools and Utilities Guide.
Example
The following example shows how to export the information about employees in Department 20 from the STAFF table in the SAMPLE database to the myfile.del file.

    CALL SYSCS_UTIL.SYSCS_EXPORT_QUERY('select * from staff where dept =20',
        'c:/output/awards.del', null, null, null);

SYSCS_UTIL.SYSCS_EXPORT_QUERY_LOBS_TO_EXTFILE system procedure
Use the SYSCS_UTIL.SYSCS_EXPORT_QUERY_LOBS_TO_EXTFILE system procedure to export the result of a SELECT statement to a main export file, and place the LOB data into a separate export file. A reference to the location of the LOB data is placed in the LOB column in the main export file.
Syntax

    SYSCS_UTIL.SYSCS_EXPORT_QUERY_LOBS_TO_EXTFILE (
        IN SELECTSTATEMENT VARCHAR(32672),
        IN FILENAME VARCHAR(32672),
        IN COLUMNDELIMITER CHAR(1),
        IN CHARACTERDELIMITER CHAR(1),
        IN CODESET VARCHAR(128)
        IN LOBSFILENAME VARCHAR(32672)
        )

When you run this procedure, the column data is written to the main export file in a delimited data file format.
SELECTSTATEMENT
Specifies the SELECT statement query that returns the data to be exported. Specifying a NULL value will result in an error. The SELECTSTATEMENT parameter takes an input argument that is a VARCHAR (32672) data type.
FILENAME
Specifies the file to which the data is to be exported. If the path is omitted, the current working directory is used. If the name of a file that already exists is specified, the export utility overwrites the contents of the file; it does not append the information. The specified location of the file should refer to the server-side location if you are using the Network Server. Specifying a NULL value results in an error. The FILENAME parameter takes an input argument that is a VARCHAR (32672) data type.
COLUMNDELIMITER
Specifies a column delimiter. The specified character is used in place of a comma to signify the end of a column. You can specify a NULL value to use the default value of a comma. The COLUMNDELIMITER parameter must be a CHAR (1) data type.
CHARACTERDELIMITER
Specifies a character delimiter. The specified character is used in place of double quotation marks to enclose a character string. You can specify a NULL value to use the default value of a double quotation mark. The CHARACTERDELIMITER parameter takes an input argument that is a CHAR (1) data type.
CODESET
Specifies the code set of the data in the export file. The code set name should be one of the Java-supported character encoding sets. Data is converted from the database code page to the specified code page before writing to the file. You can specify a NULL value to write the data in the same code page as the JVM in which it is being executed. The CODESET parameter takes an input argument that is a VARCHAR (128) data type.
LOBSFILENAME
Specifies the file that the large object data is exported to. If the path is omitted, the lob file is created in the same directory as the main export file. If you specify the name of an existing file, the export utility overwrites the contents of the file. The data is not appended to the file. If you are using the Network Server, the file should be in a server-side location. Specifying a NULL value results in an error. The LOBSFILENAME parameter takes an input argument that is a VARCHAR (32672) data type.
Usage
For additional information on using this procedure see the section "Using the bulk import and export procedures" in the Java DB Tools and Utilities Guide.
Example exporting data from a query using a separate export file for the LOB data
The following example shows how to export employee data in department 20 from the STAFF table in a sample database to the main file staff.del and the lob data to the file pictures.dat.

    CALL SYSCS_UTIL.SYSCS_EXPORT_QUERY_LOBS_TO_EXTFILE(
        'SELECT * FROM STAFF WHERE dept=20',
        'c:\data\staff.del', ',' ,'"',
        'UTF-8','c:\data\pictures.dat');

SYSCS_UTIL.SYSCS_IMPORT_DATA system procedure
The SYSCS_UTIL.SYSCS_IMPORT_DATA system procedure imports data to a subset of columns in a table. You choose the subset of columns by specifying insert columns. This procedure is also used to import a subset of column data from a file by specifying column indexes.
Syntax

    SYSCS_UTIL.SYSCS_IMPORT_DATA (IN SCHEMANAME VARCHAR(128),
    IN TABLENAME VARCHAR(128), IN INSERTCOLUMNS VARCHAR(32672),
    IN COLUMNINDEXES VARCHAR(32672), IN FILENAME VARCHAR(32672),
    IN COLUMNDELIMITER CHAR(1), IN CHARACTERDELIMITER CHAR(1),
    IN CODESET VARCHAR(128), IN REPLACE SMALLINT)

No result is returned from the procedure.
SCHEMANAME
An input argument of type VARCHAR(128) that specifies the schema of the table. Passing a NULL value will use the default schema name.
TABLENAME
An input argument of type VARCHAR (128) that specifies the table name of the table into which the data is to be imported. This table cannot be a system table or a declared temporary table. Passing a null will result in an error.
INSERTCOLUMNS
An input argument of type VARCHAR (32762) that specifies the column names (separated by commas) of the table into which the data is to be imported. Passing a NULL value will import the data into all of the columns of the table.
COLUMNINDEXES
An input argument of type VARCHAR (32762) that specifies the indexes (numbered from 1 and separated by commas) of the input data fields to be imported. Passing a NULL value will use all of the input data fields in the file.
FILENAME
An input argument of type VARCHAR(32672) that specifies the file that contains the data to be imported. If you do not specify a path, the current working directory is used. Passing a NULL value will result in an error.
COLUMNDELIMITER
An input argument of type CHAR(1) that specifies a column delimiter. The specified character is used in place of a comma to signal the end of a column. Passing a NULL value will use the default value; the default value is a comma (,).
CHARACTERDELIMITER
An input argument of type CHAR(1) that specifies a character delimiter. The specified character is used in place of double quotation marks to enclose a character string. Passing a NULL value will use the default value; the default value is a double quotation mark (").
CODESET
An input argument of type VARCHAR(128) that specifies the code set of the data in the input file. The name of the code set should be one of the Java-supported character encodings. Data is converted from the specified code set to the database code set (utf-8). Passing a NULL value will interpret the data file in the same code set as the JVM in which it is being executed.
REPLACE
A input argument of type SMALLINT. A non-zero value will run in REPLACE mode, while a value of zero will run in INSERT mode. REPLACE mode deletes all existing data from the table by truncating the data object, and inserts the imported data. The table definition and the index definitions are not changed. You can only use the REPLACE mode if the table exists. INSERT mode adds the imported data to the table without changing the existing table data. Passing a NULL will result in an error.
If you create a schema, table, or column name as a non-delimited identifier, you must pass the name to the import procedure using all uppercase characters. If you created a schema, table, or column name as a delimited identifier, you must pass the name to the import procedure using the same case that was used when it was created.
Usage
For additional information on using this procedure see the section "Using the bulk import and export procedures" in the Java DB Tools and Utilities Guide.
Example
The following example imports some of the data fields from a delimited data file called data.del into the STAFF table:

    CALL SYSCS_UTIL.SYSCS_IMPORT_DATA
        (NULL, 'STAFF', null, '1,3,4', 'data.del', null, null, null,0)

SYSCS_UTIL.SYSCS_IMPORT_DATA_LOBS_FROM_EXTFILE system procedure
Use the SYSCS_UTIL.SYSCS_IMPORT_DATA_LOBS_FROM_EXTFILE system procedure to import data to a subset of columns in a table, where the LOB data is stored in a separate file. The main import file contains all of the other data and a reference to the location of the LOB data.
Syntax

    SYSCS_UTIL.SYSCS_IMPORT_DATA_LOBS_FROM_EXTFILE (
       IN SCHEMANAME VARCHAR(128),
       IN TABLENAME VARCHAR(128),
       IN INSERTCOLUMNS VARCHAR(32672),
       IN COLUMNINDEXES VARCHAR(32672),
       IN FILENAME VARCHAR(32672),
       IN COLUMNDELIMITER CHAR(1),
       IN CHARACTERDELIMITER CHAR(1),
       IN CODESET VARCHAR(128),
       IN REPLACE SMALLINT)
       )

The import utility looks in the main import file for a reference to the location of the LOB data.
SCHEMANAME
Specifies the schema of the table. You can specify a NULL value to use the default schema name. The SCHEMANAME parameter takes an input argument that is a VARCHAR (128) data type.
TABLENAME
Specifies the name of the table into which the data is to be imported. This table cannot be a system table or a declared temporary table. The string must exactly match case of the table name. Specifying a NULL value results in an error. The TABLENAME parameter takes an input argument that is a VARCHAR (128) data type.
INSERTCOLUMNS
Specifies the comma separated column names of the table into which the data will be imported. You can specify a NULL value to import into all columns of the table. The INSERTCOLUMNS parameter takes an input argument that is a VARCHAR (32672) data type.
COLUMNINDEXES
Specifies the comma separated column indexes (numbered from one) of the input data fields that will be imported. You can specify a NULL value to use all input data fields in the file. The COLUMNINDEXES parameter takes an input argument that is a VARCHAR (32762) data type.
FILENAME
Specifies the name of the file that contains the data to be imported. If the path is omitted, the current working directory is used. The specified location of the file should refer to the server side location if using the Network Server. Specifying a NULL value results in an error. The fileName parameter takes an input argument that is a VARCHAR (32672) data type.
COLUMNDELIMITER
Specifies a column delimiter. The specified character is used in place of a comma to signify the end of a column. You can specify a NULL value to use the default value of a comma. The COLUMNDELIMITER parameter takes an input argument that is a CHAR (1) data type.
CHARACTERDELIMITER
Specifies a character delimiter. The specified character is used in place of double quotation marks to enclose a character string. You can specify a NULL value to use the default value of a double quotation mark. The CHARACTERDELIMITER parameter takes an input argument that is a CHAR (1) data type.
CODESET
Specifies the code set of the data in the input file. The code set name should be one of the Java-supported character encoding sets. Data is converted from the specified code set to the database code set (UTF-8). You can specify a NULL value to interpret the data file in the same code set as the JVM in which it is being executed. The CODESET parameter takes an input argument that is a VARCHAR (128) data type.
REPLACE
A non-zero value for the replace parameter will import in REPLACE mode, while a zero value will import in INSERT mode. REPLACE mode deletes all existing data from the table by truncating the table and inserts the imported data. The table definition and the index definitions are not changed. You can only import with REPLACE mode if the table already exists. INSERT mode adds the imported data to the table without changing the existing table data. Specifying a NULL value results in an error. The REPLACE parameter takes an input argument that is a SMALLINT data type.
If you create a schema, table, or column name as a non-delimited identifier, you must pass the name to the import procedure using all uppercase characters. If you created a schema, table, or column name as a delimited identifier, you must pass the name to the import procedure using the same case that was used when it was created.
Usage
This procedure will read the LOB data using the reference that is stored in the main import file. The format of the reference to the LOB stored in the main import file must be lobsFileName.Offset.length/.

• |  | Offset is position in the external file in bytes
• |  | length is the size of the LOB column data in bytes

For additional information on using this procedure see the section "Using the bulk import and export procedures" in the Java DB Tools and Utilities Guide.
Example importing data into specific columns, using a separate import file for the LOB data
The following example shows how to import data into several columns of the STAFF table. The STAFF table includes a LOB column in a sample database. The import file staff.del is a delimited data file. The staff.del file contains references that point to a separate file which contains the LOB data. The data in the import file is formatted using double quotation marks (") as the string delimiter and a comma (,) as the column delimiter. The data will be appended to the existing data in the STAFF table.

    CALL SYSCS_UTIL.SYSCS_IMPORT_DATA_LOBS_FROM_EXTFILE
        (null, 'STAFF', 'NAME,DEPT,SALARY,PICTURE', '2,3,4,6',
        'c:\data\staff.del', ',','"','UTF-8',  0);

SYSCS_UTIL.SYSCS_IMPORT_TABLE system procedure
The SYSCS_UTIL.SYSCS_IMPORT_TABLE system procedure imports data from an input file into all of the columns of a table. If the table receiving the imported data already contains data, you can either replace or append to the existing data.
Syntax

    SYSCS_UTIL.SYSCS_IMPORT_TABLE (IN SCHEMANAME VARCHAR(128),
    IN TABLENAME VARCHAR(128), IN FILENAME VARCHAR(32672),
    IN COLUMNDELIMITER CHAR(1), IN CHARACTERDELIMITER CHAR(1),
    IN CODESET VARCHAR(128), IN REPLACE SMALLINT)

No result is returned from the procedure.
SCHEMANAME
An input argument of type VARCHAR(128) that specifies the schema of the table. Passing a NULL value will use the default schema name.
TABLENAME
An input argument of type VARCHAR (128) that specifies the table name of the table into which the data is to be imported. This table cannot be a system table or a declared temporary table. Passing a null will result in an error.
FILENAME
An input argument of type VARCHAR(32672) that specifies the file that contains the data to be imported. If you do not specify a path, the current working directory is used. Passing a NULL value will result in an error.
COLUMNDELIMITER
An input argument of type CHAR(1) that specifies a column delimiter. The specified character is used in place of a comma to signal the end of a column. Passing a NULL value will use the default value; the default value is a comma (,).
CHARACTERDELIMITER
An input argument of type CHAR(1) that specifies a character delimiter. The specified character is used in place of double quotation marks to enclose a character string. Passing a NULL value will use the default value; the default value is a double quotation mark (").
CODESET
An input argument of type VARCHAR(128) that specifies the code set of the data in the input file. The name of the code set should be one of the Java-supported character encodings. Data is converted from the specified code set to the database code set (utf-8). Passing a NULL value will interpret the data file in the same code set as the JVM in which it is being executed.
REPLACE
A input argument of type SMALLINT. A non-zero value will run in REPLACE mode, while a value of zero will run in INSERT mode. REPLACE mode deletes all existing data from the table by truncating the data object, and inserts the imported data. The table definition and the index definitions are not changed. INSERT mode adds the imported data to the table without changing the existing table data. Passing a NULL will result in an error.
If you create a schema, table, or column name as a non-delimited identifier, you must pass the name to the import procedure using all uppercase characters. If you created a schema, table, or column name as a delimited identifier, you must pass the name to the import procedure using the same case that was used when it was created.
Usage
For additional information on using this procedure see the section "Using the bulk import and export procedures" in the Java DB Tools and Utilities Guide.
Example
The following example imports data into the STAFF table from a delimited data file called myfile.del with the percentage character (%) as the string delimiter, and a semicolon (;) as the column delimiter:

    CALL SYSCS_UTIL.SYSCS_IMPORT_TABLE
        (null, 'STAFF', 'c:/output/myfile.del', ';', '%', null,0);

SYSCS_UTIL.SYSCS_IMPORT_TABLE_LOBS_FROM_EXTFILE system procedure
Use the SYSCS_UTIL.SYSCS_IMPORT_TABLE_LOBS_FROM_EXTFILE system procedure to import data to a table, where the LOB data is stored in a separate file. The main import file contains all of the other data and a reference to the location of the LOB data.
Syntax

    SYSCS_UTIL.SYSCS_IMPORT_TABLE_LOBS_FROM_EXTFILE (
       IN SCHEMANAME VARCHAR(128),
       IN TABLENAME VARCHAR(128),
       IN FILENAME VARCHAR(32672),
       IN COLUMNDELIMITER CHAR(1),
       IN CHARACTERDELIMITER CHAR(1),
       IN CODESET VARCHAR(128),
       IN REPLACE SMALLINT)
       )

The import utility looks in the main import file for a reference to the location of the LOB data.
SCHEMANAME
Specifies the schema of the table. You can specify a NULL value to use the default schema name. The SCHEMANAME parameter takes an input argument that is a VARCHAR (128) data type.
TABLENAME
Specifies the name of the table into which the data is to be imported. This table cannot be a system table or a declared temporary table. The string must exactly match case of the table name. Specifying a NULL value results in an error. The TABLENAME parameter takes an input argument that is a VARCHAR (128) data type.
FILENAME
Specifies the name of the file that contains the data to be imported. If the path is omitted, the current working directory is used. The specified location of the file should refer to the server side location if using the Network Server. Specifying a NULL value results in an error. The FILENAME parameter takes an input argument that is a VARCHAR (32672) data type.
COLUMNDELIMITER
Specifies a column delimiter. The specified character is used in place of a comma to signify the end of a column. You can specify a NULL value to use the default value of a comma. The COLUMNDELIMITER parameter takes an input argument that is a CHAR (1) data type.
CHARACTERDELIMITER
Specifies a character delimiter. The specified character is used in place of double quotation marks to enclose a character string. You can specify a NULL value to use the default value of a double quotation mark. The CHARACTERDELIMITER parameter takes an input argument that is a CHAR (1) data type.
CODESET
Specifies the code set of the data in the input file. The code set name should be one of the Java-supported character encoding sets. Data is converted from the specified code set to the database code set (UTF-8). You can specify a NULL value to interpret the data file in the same code set as the JVM in which it is being executed. The CODESET parameter takes an input argument that is a VARCHAR (128) data type.
REPLACE
A non-zero value for the replace parameter will import in REPLACE mode, while a zero value will import in INSERT mode. REPLACE mode deletes all existing data from the table by truncating the table and inserts the imported data. The table definition and the index definitions are not changed. You can only import with REPLACE mode if the table already exists. INSERT mode adds the imported data to the table without changing the existing table data. Specifying a NULL value results in an error. The REPLACE parameter takes an input argument that is a SMALLINT data type.
If you create a schema, table, or column name as a non-delimited identifier, you must pass the name to the import procedure using all uppercase characters. If you created a schema, table, or column name as a delimited identifier, you must pass the name to the import procedure using the same case that was used when it was created.
Usage
This procedure will read the LOB data using the reference that is stored in the main import file. If you are importing from a non-Derby source, the format of the reference to the LOB stored in the main import file must be lobsFileName.Offset.length/.

• |  | Offset is position in the external file in bytes
• |  | length is the size of the LOB column data in bytes

For additional information on using this procedure see the section "Using the bulk import and export procedures" in the Java DB Tools and Utilities Guide.
Example importing data from a main import file that contains references which point to a separate file that contains LOB data
The following example shows how to import data into the STAFF table in a sample database from a delimited data file staff.del. This example defines a comma as the column delimiter. The data will be appended to the existing data in the table.

    CALL SYSCS_UTIL.SYSCS_IMPORT_TABLE_LOBS_FROM_EXTFILE(
        'APP','STAFF','c:\data\staff.del',',','"','UTF-8',0);

SYSCS_UTIL.SYSCS_FREEZE_DATABASE system procedure
The SYSCS_UTIL.SYSCS_FREEZE_DATABASE system procedure temporarily freezes the database for backup.
Syntax

    SYSCS_UTIL.SYSCS_FREEZE_DATABASE()

No result set is returned by this procedure.
Example

    String backupdirectory = "c:/mybackups/" + JCalendar.getToday();
    CallableStatement cs = conn.prepareCall
    ("CALL SYSCS_UTIL.SYSCS_FREEZE_DATABASE()");
    cs.execute();
    cs.close();
    // user supplied code to take full backup of "backupdirectory"
    // now unfreeze the database once backup has completed:
    CallableStatement cs = conn.prepareCall
    ("CALL SYSCS_UTIL.SYSCS_UNFREEZE_DATABASE()");
    cs.execute();
    cs.close();

SYSCS_UTIL.SYSCS_UNFREEZE_DATABASE system procedure
The SYSCS_UTIL.SYSCS_UNFREEZE_DATABASE system procedure unfreezes a database after backup.
Syntax

    SYSCS_UTIL.SYSCS_UNFREEZE_DATABASE()

No result set is returned by this procedure.
Example

    String backupdirectory = "c:/mybackups/" + JCalendar.getToday();
    CallableStatement cs = conn.prepareCall
    ("CALL SYSCS_UTIL.SYSCS_FREEZE_DATABASE()");
    cs.execute();
    cs.close();
    // user supplied code to take full backup of "backupdirectory"
    // now unfreeze the database once backup has completed:
    CallableStatement cs = conn.prepareCall
    ("CALL SYSCS_UTIL.SYSCS_UNFREEZE_DATABASE()");
    cs.execute();
    cs.close();

SYSCS_UTIL.SYSCS_RELOAD_SECURITY_POLICY system procedure
The SYSCS_UTIL.SYSCS_RELOAD_SECURITY_POLICY system procedure reloads the security policy, allowing you to fine-tune your Java security on the fly. For more information on security policies, see the section titled "Running the Network Server under the security manager" in the Java DB Server and Administration Guide and the section titled "Running Derby under a security manager" in the Java DB Developer's Guide.
Syntax

    SYSCS_UTIL.SYSCS_RELOAD_SECURITY_POLICY()

No result set is returned by this procedure.
Example

    CallableStatement cs = conn.prepareCall
    ("CALL SYSCS_UTIL.SYSCS_RELOAD_SECURITY_POLICY()");
    cs.execute();
    cs.close();

SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY system procedure
Use the SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY system procedure to set or delete the value of a property of the database on the current connection.
If "VALUE" is not null, then the property with key value "KEY" is set to "VALUE". If "VALUE" is null, then the property with key value "KEY" is deleted from the database property set.
Syntax

    SYSCS_UTIL.SYSCS_GET_DATABASE_PROPERTY(IN KEY VARCHAR(128),
    IN VALUE VARCHAR(32672))

This procedure does not return any results.
JDBC example
Set the derby.locks.deadlockTimeout property to a value of 10:

    CallableStatement cs = conn.prepareCall
    ("CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY(?, ?)");
    cs.setString(1, "derby.locks.deadlockTimeout");
    cs.setString(2, "10");
    cs.execute();
    cs.close();

SQL example
Set the derby.locks.deadlockTimeout property to a value of 10:

    CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY
    ('derby.locks.deadlockTimeout', '10');

SYSCS_UTIL.SYSCS_SET_RUNTIMESTATISTICS system procedure
The SYSCS_UTIL.SYSCS_SET_RUNTIMESTATISTICS() system procedure turns a connection's runtime statistics on or off. By default, the runtime statistics are turned off. When the runtimestatistics attribute is turned on, Derby maintains information about the execution plan for each statement executed within the connection (except for COMMIT) until the attribute is turned off. To turn the runtimestatistics attribute off, call the procedure with an argument of zero. To turn the runtimestatistics on, call the procedure with any non-zero argument.
For statements that do not return rows, the object is created when all internal processing has completed before returning to the client program. For statements that return rows, the object is created when the first next() call returns 0 rows or if a close() call is encountered, whichever comes first.
Syntax

    SYSCS_UTIL.SYSCS_SET_RUNTIMESTATISTICS(IN SMALLINT ENABLE)

Example

    -- establish a connection
    -- turn on RUNTIMESTATISTIC for connection:
    CALL SYSCS_UTIL.SYSCS_SET_RUNTIMESTATISTICS(1);
    -- execute complex query here
    -- step through the result sets
    -- access runtime statistics information:
    CALL SYSCS_UTIL.SYSCS_SET_RUNTIMESTATISTICS(0);

SYSCS_UTIL.SYSCS_SET_STATISTICS_TIMING system procedure
Statistics timing is an attribute associated with a connection that you turn on and off by using the SYSCS_UTIL.SYSCS_SET_STATISTICS_TIMING system procedure. Statistics timing is turned off by default. Turn statistics timing on only when the runtimestatistics attribute is already on. Turning statistics timing on when the runtimestatistics attribute is off has no effect.
Turn statistics timing on by calling this procedure with a non-zero argument. Turn statistics timing off by calling the procedure with a zero argument.
When statistics timing is turned on, Derby tracks the timings of various aspects of the execution of a statement. This information is included in the information returned by the SYSCS_UTIL.SYSCS_GET_RUNTIMESTATISTICS system function. When statistics timing is turned off, the SYSCS_UTIL.SYSCS_GET_RUNTIMESTATISTICS system function shows all timing values as zero.
Syntax

    SYSCS_UTIL.SYSCS_SET_STATISTICS_TIMING(IN SMALLINT ENABLE)

Example
To turn the runtimestatistics attribute and then the statistics timing attribute on:

    CALL SYSCS_UTIL.SYSCS_SET_RUNTIMESTATISTICS(1);
    CALL SYSCS_UTIL.SYSCS_SET_STATISTICS_TIMING(1);

SYSCS_DIAG diagnostic tables and functions
Derby provides a set of system table expressions which you can use to obtain diagnostic information about the state of the database and about the database sessions.
There are two types of diagnostic table expressions in Derby:
Diagnostic tables
Tables that are like any other table in Derby. You can specify the diagnostic table name anywhere a normal table name is allowed.
Diagnostic table functions
Functions that are like any other function in Derby. Diagnostic table functions can accept zero or more arguments, depending on the table function that you use. You must use the SQL-defined table function syntax to access these functions.
The following table shows the types and names of the diagnostic table expressions in Derby.
Table 9. System diagnostic table expressions provided by Derby

Diagnostic table expression | Type of expression
SYSCS_DIAG.ERROR_LOG_READER | Table function
SYSCS_DIAG.ERROR_MESSAGES | Table
SYSCS_DIAG.LOCK_TABLE | Table
SYSCS_DIAG.SPACE_TABLE | Table function
SYSCS_DIAG.STATEMENT_CACHE | Table
SYSCS_DIAG.STATEMENT_DURATION | Table function
SYSCS_DIAG.TRANSACTION_TABLE | Table

Restriction: If you reference a diagnostic table in a DDL statement or a compression procedure, Derby returns an exception.
SYSCS_DIAG.ERROR_LOG_READER diagnostic table function
The SYSCS_DIAG.ERROR_LOG_READER diagnostic table function contains all the useful SQL statements that are in the derby.log file or a log file that you specify.
One use of this diagnostic table function is to determine the active transactions and the SQL statements in those transactions at a given point in time. For example, if a deadlock or lock timeout occurred you can find the timestamp (timestampConstant) in the error log.
To access the SYSCS_DIAG.ERROR_LOG_READER diagnostic table function, you must use the SQL table function syntax.
For example:

    SELECT *
        FROM TABLE (SYSCS_DIAG.ERROR_LOG_READER())
        AS T1

where T1 is a user-specified table name that is any valid identifier.
You can specify a log file name as an optional argument to the SYSCS_DIAG.ERROR_LOG_READER diagnostic table function. When you specify a log file name, the file name must be an expression whose data type maps to a Java string.
For example:

    SELECT *
        FROM TABLE (SYSCS_DIAG.ERROR_LOG_READER('myderbyerrors.log'))
        AS T1

Tip: By default Derby log files contain only boot, shutdown, and error messages. In the Tuning Java DB guide, see the derby.stream.error.logSeverityLevel property and the derby.language.logStatementText property for instructions on how to print more information to Derby log files. You can then query that information by using the SYSCS_DIAG.ERROR_LOG_READER diagnostic table function.
SYSCS_DIAG.ERROR_MESSAGES diagnostic table
The SYSCS_DIAG.ERROR_MESSAGES diagnostic table shows all of the SQLStates, locale-sensitive error messages, and exception severities for a Derby database. You can reference the SYSCS_DIAG.ERROR_MESSAGES diagnostic table directly in a statement.
For example:

    SELECT * FROM SYSCS_DIAG.ERROR_MESSAGES

SYSCS_DIAG.LOCK_TABLE diagnostic table
The SYSCS_DIAG.LOCK_TABLE diagnostic table shows all of the locks that are currently held in the Derby database. You can reference the SYSCS_DIAG.LOCK_TABLE diagnostic table directly in a statement.
For example:

    SELECT * FROM SYSCS_DIAG.LOCK_TABLE

When the SYSCS_DIAG.LOCK_TABLE diagnostic table is referenced in a statement, a snap shot of the lock table is taken. A snap shot is used so that referencing the diagnostic table does not alter the normal timing and flow of the application. It is possible that some locks will be in a transition state when the snap shot is taken.
SYSCS_DIAG.SPACE_TABLE diagnostic table function
The SYSCS_DIAG.SPACE_TABLE diagnostic table function shows the space usage of a particular table and its indexes. You can use this diagnostic table function to determine if space might be saved by compressing the table and indexes.
To access the SYSCS_DIAG.SPACE_TABLE diagnostic table function, you must use the SQL table function syntax. This diagnostic table function takes two arguments, the schemaName and the tableName. The tableName argument is required. If you do not specify the schemaName, the current schema is used.
For example, use the following query to return the space usage for all of the user tables and indexes in the database:

    SELECT T2.*
        FROM
            SYS.SYSTABLES systabs,
            TABLE (SYSCS_DIAG.SPACE_TABLE(systabs.tablename)) AS T2
        WHERE systabs.tabletype = 'T'

where T2 is a user-specified table name that is any valid identifier.
Both the schemaName and the tableName arguments must be expressions whose data types map to Java strings. If the schemaName and the tableName are non-delimited identifiers, you must specify the names in upper case.
For example:

    SELECT *
        FROM TABLE (SYSCS_DIAG.SPACE_TABLE('MYSCHEMA', 'MYTABLE'))
        AS T2

SYSCS_DIAG.STATEMENT_CACHE diagnostic table
The SYSCS_DIAG.STATEMENT_CACHE diagnostic table shows the contents of the SQL statement cache. You can reference the SYSCS_DIAG.STATEMENT_CACHE diagnostic table directly in a statement.
For example:

    SELECT * FROM SYSCS_DIAG.STATEMENT_CACHE

SYSCS_DIAG.STATEMENT_DURATION diagnostic table function
You can use the SYSCS_DIAG.STATEMENT_DURATION diagnostic table function to analyze the execution duration of the useful SQL statements in the derby.log file or a log file that you specify.
You can also use this diagnostic table function to get an indication of where the bottlenecks are in the JDBC code for an application.
To access the SYSCS_DIAG.STATEMENT_DURATION diagnostic table function, you must use the SQL table function syntax.
For example:

    SELECT *
        FROM TABLE (SYSCS_DIAG.STATEMENT_DURATION())
        AS T1

where T1 is a user-specified table name that is any valid identifier.
Restriction: For each transaction ID, a row is not returned for the last statement with that transaction id. Transaction IDs change within a connection after a commit or rollback, if the transaction that just ended modified data.
You can specify a log file name as an optional argument to the SYSCS_DIAG.STATEMENT_DURATION diagnostic table function. When you specify a log file name, the file name must be an expression whose data type maps to a Java string.
For example:

    SELECT *
        FROM TABLE (SYSCS_DIAG.STATEMENT_DURATION('somederby.log'))
        AS T1

Tip: By default Derby log files contain only boot, shutdown, and error messages. In the Tuning Java DB guide, see the derby.stream.error.logSeverityLevel property and the derby.language.logStatementText property for instructions on how to print more information to Derby log files. You can then query that information by using the SYSCS_DIAG.STATEMENT_DURATION diagnostic table function.
SYSCS_DIAG.TRANSACTION_TABLE diagnostic table
The SYSCS_DIAG.TRANSACTION_TABLE diagnostic table shows all of the transactions that are currently in the database. You can reference the SYSCS_DIAG.TRANSACTION_TABLE diagnostic table directly in a statement.
For example:

    SELECT * FROM SYSCS_DIAG.TRANSACTION_TABLE

When the SYSCS_DIAG.TRANSACTION_TABLE diagnostic table is referenced in a statement, a snap shot of the transaction table is taken. A snap shot is used so that referencing the diagnostic table does not alter the normal timing and flow of the application. It is possible that some transactions will be in a transition state when the snap shot is taken.
Data types
This section describes the data types used in Derby.
Built-In type overview
The SQL type system is used by the language compiler to determine the compile-time type of an expression and by the language execution system to determine the runtime type of an expression, which can be a subtype or implementation of the compile-time type.
Each type has associated with it values of that type. In addition, values in the database or resulting from expressions can be NULL, which means the value is missing or unknown. Although there are some places where the keyword NULL can be explicitly used, it is not in itself a value, because it needs to have a type associated with it.
The syntax presented in this section is the syntax you use when specifying a column's data type in a CREATE TABLE statement.
Numeric types
Numeric types used in Derby.
Numeric type overview
Numeric types include the following types, which provide storage of varying sizes:

• |  | Integer numerics
• |  | SMALLINT (2 bytes)
• |  | INTEGER (4 bytes)
• |  | BIGINT (8 bytes)
• |  | Approximate or floating-point numerics
• |  | REAL (4 bytes)
• |  | DOUBLE PRECISION (8 bytes)
• |  | FLOAT (an alias for DOUBLE PRECISION or REAL)
• |  | Exact numeric
• |  | DECIMAL (storage based on precision)
• |  | NUMERIC (an alias for DECIMAL)

Numeric type promotion in expressions
In expressions that use only integer types, Derby promotes the type of the result to at least INTEGER. In expressions that mix integer with non-integer types, Derby promotes the result of the expression to the highest type in the expression. Type Promotion in Expressions shows the promotion of data types in expressions.
Table 10. Type Promotion in Expressions

Largest Type That Appears in Expression | Resulting Type of Expression
DOUBLE PRECISION | DOUBLE PRECISION
REAL | DOUBLE PRECISION
DECIMAL | DECIMAL
BIGINT | BIGINT
INTEGER | INTEGER
SMALLINT | INTEGER

For example:

    -- returns a double precision
    VALUES 1 + 1.0e0
    -- returns a decimal
    VALUES 1 + 1.0
    -- returns an integer
    VALUES CAST (1 AS INT) + CAST (1 AS INT)

Storing values of one numeric data type in columns of another numeric data type
An attempt to put a floating-point type of a larger storage size into a location of a smaller size fails only if the value cannot be stored in the smaller-size location. For example:

    create table mytable (r REAL, d DOUBLE PRECISION);
    0 rows inserted/updated/deleted
    INSERT INTO mytable (r, d) values (3.4028236E38, 3.4028235E38);
    ERROR X0X41: The number '3.4028236E38' is outside the range for
    the data type REAL.

You can store a floating point type in an INTEGER column; the fractional part of the number is truncated. For example:

    INSERT INTO mytable(integer_column) values (1.09e0);
    1 row inserted/updated/deleted
    SELECT integer_column
    FROM mytable;
    I
    ---------------
    1

Integer types can always be placed successfully in approximate numeric values, although with the possible loss of some precision.
Integers can be stored in decimals if the DECIMAL precision is large enough for the value. For example:

    ij> insert into mytable (decimal_column)
    VALUES (55555555556666666666);
    ERROR X0Y21: The number '55555555556666666666' is outside the
    range of the target DECIMAL/NUMERIC(5,2) datatype.

An attempt to put an integer value of a larger storage size into a location of a smaller size fails if the value cannot be stored in the smaller-size location. For example:

    INSERT INTO mytable (int_column) values 2147483648;
    ERROR 22003: The resulting value is outside the range for the
    data type INTEGER.

Note: When truncating trailing digits from a NUMERIC value, Derby rounds down.
Scale for decimal arithmetic
SQL statements can involve arithmetic expressions that use decimal data types of different precisions (the total number of digits, both to the left and to the right of the decimal point) and scales (the number of digits of the fractional component). The precision and scale of the resulting decimal type depend on the precision and scale of the operands.
Given an arithmetic expression that involves two decimal operands:

• |  | lp stands for the precision of the left operand
• |  | rp stands for the precision of the right operand
• |  | ls stands for the scale of the left operand
• |  | rs stands for the scale of the right operand

Use the following formulas to determine the scale of the resulting data type for the following kinds of arithmetical expressions:

• |  | multiplication ls + rs
• |  | division 31 - lp + ls - rs
• |  | AVG() max(max(ls, rs), 4)
• |  | all others max(ls, rs)

For example, the scale of the resulting data type of the following expression is 27:

    11.0/1111.33
    // 31 - 3 + 1 - 2 = 27

Use the following formulas to determine the precision of the resulting data type for the following kinds of arithmetical expressions:

• |  | multiplication lp + rp
• |  | addition 2 * (p - s) + s
• |  | division lp - ls + rp + max(ls + rp - rs + 1, 4)
• |  | all others max(lp - ls, rp - rs) + 1 + max(ls, rs)

Data type assignments and comparison, sorting, and ordering
Table 11. Assignments allowed by Derby
This table displays valid assignments between data types in Derby. A "Y" indicates that the assignment is valid.

Types |
    S
    M
    A
    L
    L
    I
    N
    T
    I
    N
    T
    E
    G
    E
    R
    B
    I
    G
    I
    N
    T
    D
    E
    C
    I
    M
    A
    L
    R
    E
    A
    L
    D
    O
    U
    B
    L
    E
    F
    L
    O
    A
    T
    C
    H
    A
    R
    V
    A
    R
    C
    H
    A
    R
    L
    O
    N
    G

    V
    A
    R
    C
    H
    A
    R
    C
    H
    A
    R

    F
    O
    R

    B
    I
    T

    D
    A
    T
    A
    V
    A
    R
    C
    H
    A
    R

    F
    O
    R

    B
    I
    T

    D
    A
    T
    A
    L
    O
    N
    G

    V
    A
    R
    C
    H
    A
    R

    F
    O
    R

    B
    I
    T

    D
    A
    T
    A
    C
    L
    O
    B
    B
    L
    O
    B
    D
    A
    T
    E
    T
    I
    M
    E
    T
    I
    M
    E
    S
    T
    A
    M
    P
    X
    M
    L
SMALL INT | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
INTEGER | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
BIGINT | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
DECIMAL | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
REAL | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
DOUBLE | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
FLOAT | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
CHAR | - | - | - | - | - | - | - | Y | Y | Y | - | - | - | Y | - | Y | Y | Y | -
VARCHAR | - | - | - | - | - | - | - | Y | Y | Y | - | - | - | Y | - | Y | Y | Y | -
LONG VARCHAR | - | - | - | - | - | - | - | Y | Y | Y | - | - | - | Y | - | - | - | - | -
CHAR FOR BIT DATA | - | - | - | - | - | - | - | - | - | - | Y | Y | Y | - | - | - | - | - | -
VARCHAR FOR BIT DATA | - | - | - | - | - | - | - | - | - | - | Y | Y | Y | - | - | - | - | - | -
LONG VARCHAR FOR BIT DATA | - | - | - | - | - | - | - | - | - | - | Y | Y | Y | - | - | - | - | - | -
CLOB | - | - | - | - | - | - | - | Y | Y | Y | - | - | - | Y | - | - | - | - | -
BLOB | - | - | - | - | - | - | - | - | - | - | - | - | - | - | Y | - | - | - | -
DATE | - | - | - | - | - | - | - | Y | Y | - | - | - | - | - | - | Y | - | - | -
TIME | - | - | - | - | - | - | - | Y | Y | - | - | - | - | - | - | - | Y | - | -
TIME STAMP | - | - | - | - | - | - | - | Y | Y | - | - | - | - | - | - | - | - | Y | -
XML | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | Y

Table 12. Comparisons allowed by Derby
This table displays valid comparisons between data types in Derby. A "Y" indicates that the comparison is allowed.

Types |
    S
    M
    A
    L
    L
    I
    N
    T
    I
    N
    T
    E
    G
    E
    R
    B
    I
    G
    I
    N
    T
    D
    E
    C
    I
    M
    A
    L
    R
    E
    A
    L
    D
    O
    U
    B
    L
    E
    F
    L
    O
    A
    T
    C
    H
    A
    R
    V
    A
    R
    C
    H
    A
    R
    L
    O
    N
    G

    V
    A
    R
    C
    H
    A
    R
    C
    H
    A
    R

    F
    O
    R

    B
    I
    T

    D
    A
    T
    A
    V
    A
    R
    C
    H
    A
    R

    F
    O
    R

    B
    I
    T

    D
    A
    T
    A
    L
    O
    N
    G

    V
    A
    R
    C
    H
    A
    R

    F
    O
    R

    B
    I
    T

    D
    A
    T
    A
    C
    L
    O
    B
    B
    L
    O
    B
    D
    A
    T
    E
    T
    I
    M
    E
    T
    I
    M
    E
    S
    T
    A
    M
    P
    X
    M
    L
SMALL INT | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
INTEGER | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
BIGINT | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
DECIMAL | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
REAL | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
DOUBLE | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
FLOAT | Y | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | -
CHAR | - | - | - | - | - | - | - | Y | Y | - | - | - | - | - | - | Y | Y | Y | -
VARCHAR | - | - | - | - | - | - | - | Y | Y | - | - | - | - | - | - | Y | Y | Y | -
LONG VARCHAR | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | -
CHAR FOR BIT DATA | - | - | - | - | - | - | - | - | - | - | Y | Y | - | - | - | - | - | - | -
VARCHAR FOR BIT DATA | - | - | - | - | - | - | - | - | - | - | Y | Y | - | - | - | - | - | - | -
LONG VARCHAR FOR BIT DATA | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | -
CLOB | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | -
BLOB | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | -
DATE | - | - | - | - | - | - | - | Y | Y | - | - | - | - | - | - | Y | - | - | -
TIME | - | - | - | - | - | - | - | Y | Y | - | - | - | - | - | - | - | Y | - | -
TIME STAMP | - | - | - | - | - | - | - | Y | Y | - | - | - | - | - | - | - | - | Y | -
XML | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | -

BIGINT data type
BIGINT provides 8 bytes of storage for integer values.
Syntax

    BIGINT

Corresponding compile-time Java type
java.lang.Long
JDBC metadata type (java.sql.Types)
BIGINT
Minimum value
-9223372036854775808 (java.lang.Long.MIN_VALUE)
Maximum value
9223372036854775807 (java.lang.Long.MAX_VALUE)
When mixed with other data types in expressions, the resulting data type follows the rules shown in Numeric type promotion in expressions.
An attempt to put an integer value of a larger storage size into a location of a smaller size fails if the value cannot be stored in the smaller-size location. Integer types can always successfully be placed in approximate numeric values, although with the possible loss of some precision. BIGINTs can be stored in DECIMALs if the DECIMAL precision is large enough for the value.

    9223372036854775807

BLOB data type
A BLOB (binary large object) is a varying-length binary string that can be up to 2,147,483,647 characters long. Like other binary types, BLOB strings are not associated with a code page. In addition, BLOB strings do not hold character data.
The length is given in bytes for BLOB unless one of the suffixes K, M, or G is given, relating to the multiples of 1024, 1024*1024, 1024*1024*1024 respectively.
Note: Length is specified in bytes for BLOB.
Syntax

    { BLOB | BINARY LARGE OBJECT } [ ( length [{K |M |G }] ) ]

Default
A BLOB without a specified length is defaulted to two gigabytes (2,147,483,647).
Corresponding compile-time Java type
java.sql.Blob
JDBC metadata type (java.sql.Types)
BLOB
Use the getBlob method on the java.sql.ResultSet to retrieve a BLOB handle to the underlying data.
Related information
see Mapping of java.sql.Blob and java.sql.Clob interfaces

    create table pictures(name varchar(32) not null primary key, pic blob(16M));

    --find all logotype pictures
    select length(pic), name from pictures where name like '%logo%';

    --find all image doubles (blob comparsions)
    select a.name as double_one, b.name as double_two
    from pictures as a, pictures as b
    where a.name < b.name
    and a.pic = b.pic
    order by 1,2;

CHAR data type
CHAR provides for fixed-length storage of strings.
Syntax

    CHAR[ACTER] [(length)]

length is an unsigned integer constant. The default length for a CHAR is 1.
Corresponding compile-time Java type
java.lang.String
JDBC metadata type (java.sql.Types)
CHAR
Derby inserts spaces to pad a string value shorter than the expected length. Derby truncates spaces from a string value longer than the expected length. Characters other than spaces cause an exception to be raised. When comparison boolean operators are applied to CHARs, the shorter string is padded with spaces to the length of the longer string.
When CHARs and VARCHARs are mixed in expressions, the shorter value is padded with spaces to the length of the longer value.
The type of a string constant is CHAR.
Implementation-defined aspects
The only limit on the length of CHAR data types is the value java.lang.Integer.MAX_VALUE.

    -- within a string constant use two single quotation marks
    -- to represent a single quotation mark or apostrophe
    VALUES 'hello this is Joe''s string'

CHAR FOR BIT DATA data type
A CHAR FOR BIT DATA type allows you to store byte strings of a specified length. It is useful for unstructured data where character strings are not appropriate.
Syntax

    { CHAR | CHARACTER }[(length)] FOR BIT DATA

length is an unsigned integer literal designating the length in bytes.
The default length for a CHAR FOR BIT DATA type is 1., and the maximum size of length is 254 bytes.
JDBC metadata type (java.sql.Types)
BINARY
CHAR FOR BIT DATA stores fixed-length byte strings. If a CHAR FOR BIT DATA value is smaller than the target CHAR FOR BIT DATA, it is padded with a 0x20 byte value.
Comparisons of CHAR FOR BIT DATA and VARCHAR FOR BIT DATA values are precise. For two bit strings to be equal, they must be exactly the same length. (This differs from the way some other DBMSs handle BINARY values but works as specified in SQL-92.)
An operation on a VARCHAR FOR BIT DATA and a CHAR FOR BIT DATA value (e.g., a concatenation) yields a VARCHAR FOR BIT DATA value.

    CREATE TABLE t (b CHAR(2) FOR BIT DATA);
    INSERT INTO t VALUES (X'DE');
    SELECT *
    FROM t;
    -- yields the following output
    B
    -----
    de20

CLOB data type
A CLOB (character large object) value can be up to 2,147,483,647 characters long. A CLOB is used to store unicode character-based data, such as large documents in any character set.
The length is given in number characters for both CLOB, unless one of the suffixes K, M, or G is given, relating to the multiples of 1024, 1024*1024, 1024*1024*1024 respectively.
Length is specified in characters (unicode) for CLOB.
Syntax

    {CLOB |CHARACTER LARGE OBJECT} [ ( length [{K |M |G}] ) ]

Default
A CLOB without a specified length is defaulted to two gigabytes (2,147,483,647).
Corresponding Compile-Time Java Type
java.sql.Clob
JDBC Metadata Type (java.sql.Types)
CLOB
Use the getClob method on the java.sql.ResultSet to retrieve a CLOB handle to the underlying data.
Related Information
See Mapping of java.sql.Blob and java.sql.Clob interfaces.

    import java.sql.*;

    public class clob
    {
    	public static void main(String[] args) {
    		try {
    			String url = "jdbc:derby:clobberyclob;create=true";

    			Class.forName("org.apache.derby.jdbc.EmbeddedDriver").newInstance();
    			Connection conn = DriverManager.getConnection(url);

                Statement s = conn.createStatement();
                s.executeUpdate("CREATE TABLE documents (id INT, text CLOB(64 K))");
                conn.commit();

                // --- add a file
                java.io.File file = new java.io.File("asciifile.txt");
                int fileLength = (int) file.length();

                // - first, create an input stream
                java.io.InputStream fin = new java.io.FileInputStream(file);
                PreparedStatement ps = conn.prepareStatement("INSERT
                INTO documents VALUES (?, ?)");
                ps.setInt(1, 1477);

                // - set the value of the input parameter to the input stream
                ps.setAsciiStream(2, fin, fileLength);
                ps.execute();
                conn.commit();

                // --- reading the columns
                ResultSet rs = s.executeQuery("SELECT text FROM documents
                 WHERE id = 1477");
                while (rs.next()) {
                    java.sql.Clob aclob = rs.getClob(1);
                    java.io.InputStream ip = rs.getAsciiStream(1);
                    int c = ip.read();
                    while (c > 0) {
                        System.out.print((char)c);
                        c = ip.read();
                    }
                    System.out.print("\n");
                    // ...
                }
            } catch (Exception e) {
                System.out.println("Error! "+e);
            }
        }
    }

DATE data type
DATE provides for storage of a year-month-day in the range supported by java.sql.Date.
Syntax

    DATE

Corresponding compile-time Java type
java.sql.Date
JDBC metadata type (java.sql.Types)
DATE
Dates, times, and timestamps must not be mixed with one another in expressions.
Any value that is recognized by the java.sql.Date method is permitted in a column of the corresponding SQL date/time data type. Derby supports the following formats for DATE:

    yyyy-mm-dd
    mm/dd/yyyy
    dd.mm.yyyy

The first of the three formats above is the java.sql.Date format.
The year must always be expressed with four digits, while months and days may have either one or two digits.
Derby also accepts strings in the locale specific datetime format, using the locale of the database server. If there is an ambiguity, the built-in formats above take precedence.
Examples

    VALUES DATE('1994-02-23')

    VALUES '1993-09-01'

DECIMAL data type
DECIMAL provides an exact numeric in which the precision and scale can be arbitrarily sized. You can specify the precision (the total number of digits, both to the left and the right of the decimal point) and the scale (the number of digits of the fractional component). The amount of storage required is based on the precision.
Syntax

    { DECIMAL | DEC } [(precision [, scale ])]

The precision must be between 1 and 31. The scale must be less than or equal to the precision.
If the scale is not specified, the default scale is 0. If the precision is not specified, the default precision is 5.
An attempt to put a numeric value into a DECIMAL is allowed as long as any non-fractional precision is not lost. When truncating trailing digits from a DECIMAL value, Derby rounds down.
For example:

    -- this cast loses only fractional precision
    values cast (1.798765 AS decimal(5,2));
    1
    --------
    1.79
    -- this cast does not fit
    values cast (1798765 AS decimal(5,2));
    1
    --------
    ERROR 22003: The resulting value is outside the range
    for the data type DECIMAL/NUMERIC(5,2).

When mixed with other data types in expressions, the resulting data type follows the rules shown in Numeric type promotion in expressions.
See also Storing values of one numeric data type in columns of another numeric data type.
When two decimal values are mixed in an expression, the scale and precision of the resulting value follow the rules shown in Scale for decimal arithmetic.
Corresponding compile-time Java type
java.math.BigDecimal
JDBC metadata type (java.sql.Types)
DECIMAL

    VALUES 123.456

    VALUES 0.001

Integer constants too big for BIGINT are made DECIMAL constants.
DOUBLE data type
The DOUBLE data type is a synonym for the DOUBLE PRECISION data type.
Syntax

    DOUBLE

DOUBLE PRECISION data type
The DOUBLE PRECISION data type provides 8-byte storage for numbers using IEEE floating-point notation.
Syntax

    DOUBLE PRECISION

or, alternately

    DOUBLE

DOUBLE can be used synonymously with DOUBLE PRECISION.
Limitations
DOUBLE value ranges:

• |  | Smallest DOUBLE value: -1.79769E+308
• |  | Largest DOUBLE value: 1.79769E+308
• |  | Smallest positive DOUBLE value: 2.225E-307
• |  | Largest negative DOUBLE value: -2.225E-307

These limits are different from the java.lang.DoubleJava type limits.
An exception is thrown when any double value is calculated or entered that is outside of these value ranges. Arithmetic operations do not round their resulting values to zero. If the values are too small, you will receive an exception.
Numeric floating point constants are limited to a length of 30 characters.

    -- this example will fail because the constant is too long:
    values 01234567890123456789012345678901e0;

Corresponding compile-time Java type
java.lang.Double
JDBC metadata type (java.sql.Types)
DOUBLE
When mixed with other data types in expressions, the resulting data type follows the rules shown in Numeric type promotion in expressions.
See also Storing values of one numeric data type in columns of another numeric data type.
Examples

    3421E+09
    425.43E9
    9E-10
    4356267544.32333E+30

FLOAT data type
The FLOAT data type is an alias for a REAL or DOUBLE PRECISION data type, depending on the precision you specify.
Syntax

    FLOAT [ (precision) ]

The default precision for FLOAT is 53 and is equivalent to DOUBLE PRECISION. A precision of 23 or less makes FLOAT equivalent to REAL. A precision of 24 or greater makes FLOAT equivalent to DOUBLE PRECISION. If you specify a precision of 0, you get an error. If you specify a negative precision, you get a syntax error.
JDBC metadata type (java.sql.Types)
REAL or DOUBLE
Limitations
If you are using a precision of 24 or greater, the limits of FLOAT are similar to the limits of DOUBLE.
If you are using a precision of 23 or less, the limits of FLOAT are similar to the limits of REAL.
INTEGER data type
INTEGER provides 4 bytes of storage for integer values.
Syntax

    { INTEGER | INT }

Corresponding Compile-Time Java Type
java.lang.Integer
JDBC Metadata Type (java.sql.Types)
INTEGER
Minimum Value
-2147483648 (java.lang.Integer.MIN_VALUE)
Maximum Value
2147483647 (java.lang.Integer.MAX_VALUE)
When mixed with other data types in expressions, the resulting data type follows the rules shown in Numeric type promotion in expressions.
See also Storing values of one numeric data type in columns of another numeric data type.

    3453
    425

LONG VARCHAR data type
The LONG VARCHAR type allows storage of character strings with a maximum length of 32,700 characters. It is identical to VARCHAR, except that you do not have to specify a maximum length when creating columns of this type.
Syntax

    LONG VARCHAR

Corresponding compile-time Java type
java.lang.String
JDBC metadata type (java.sql.Types)
LONGVARCHAR
When you are converting from Java values to SQL values, no Java type corresponds to LONG VARCHAR.
LONG VARCHAR FOR BIT DATA data type
The LONG VARCHAR FOR BIT DATA type allows storage of bit strings up to 32,700 bytes. It is identical to VARCHAR FOR BIT DATA, except that you do not have to specify a maximum length when creating columns of this type.
Syntax

    LONG VARCHAR FOR BIT DATA

JDBC metadata type (java.sql.Types)
LONGVARBINARY
NUMERIC data type
NUMERIC is a synonym for DECIMAL and behaves the same way. See DECIMAL data type.
Syntax

    NUMERIC [(precision [, scale ])]

Corresponding compile-time Java type
java.math.BigDecimal
JDBC metadata Ttype (java.sql.Types)
NUMERIC

    123.456
    .001

REAL data type
The REAL data type provides 4 bytes of storage for numbers using IEEE floating-point notation.
Syntax

    REAL

Corresponding compile-time Java type
java.lang.Float
JDBC metadata type (java.sql.Types)
REAL
Limitations
REAL value ranges:

• |  | Smallest REAL value: -3.402E+38
• |  | Largest REAL value: 3.402E+38
• |  | Smallest positive REAL value: 1.175E-37
• |  | Largest negative REAL value: -1.175E-37

These limits are different from the java.lang.Float Java type limits.
An exception is thrown when any double value is calculated or entered that is outside of these value ranges. Arithmetic operations do not round their resulting values to zero. If the values are too small, you will receive an exception. The arithmetic operations take place with double arithmetic in order to detect under flows.
Numeric floating point constants are limited to a length of 30 characters.

    -- this example will fail because the constant is too long:
    values 01234567890123456789012345678901e0;

When mixed with other data types in expressions, the resulting data type follows the rules shown in Numeric type promotion in expressions.
See also Storing values of one numeric data type in columns of another numeric data type.
Constants always map to DOUBLE PRECISION; use a CAST to convert a constant to a REAL.
SMALLINT data type
SMALLINT provides 2 bytes of storage.
Syntax

    SMALLINT

Corresponding compile-time Java type
java.lang.Short
JDBC metadata type (java.sql.Types)
SMALLINT
Minimum value
-32768 (java.lang.Short.MIN_VALUE)
Maximum value
32767 (java.lang.Short.MAX_VALUE)
When mixed with other data types in expressions, the resulting data type follows the rules shown in Numeric type promotion in expressions.
See also Storing values of one numeric data type in columns of another numeric data type.
Constants in the appropriate format always map to INTEGER or BIGINT, depending on their length.
TIME data type
TIME provides for storage of a time-of-day value.
Syntax

    TIME

Corresponding compile-time Java type
java.sql.Time
JDBC metadata type (java.sql.Types)
TIME
Dates, times, and timestamps cannot be mixed with one another in expressions except with a CAST.
Any value that is recognized by the java.sql.Time method is permitted in a column of the corresponding SQL date/time data type. Derby supports the following formats for TIME:

    hh:mm[:ss]
    hh.mm[.ss]
    hh[:mm] {AM | PM}

The first of the three formats above is the java.sql.Time format.
Hours may have one or two digits. Minutes and seconds, if present, must have two digits.
Derby also accepts strings in the locale specific datetime format, using the locale of the database server. If there is an ambiguity, the built-in formats above take precedence.
Examples

    VALUES TIME('15:09:02')
    VALUES '15:09:02'

TIMESTAMP data type
TIMESTAMP stores a combined DATE and TIME value to be stored. It permits a fractional-seconds value of up to nine digits.
Syntax

    TIMESTAMP

Corresponding compile-time Java type
java.sql.Timestamp
JDBC metadata type (java.sql.Types)
TIMESTAMP
Dates, times, and timestamps cannot be mixed with one another in expressions.
Derby supports the following formats for TIMESTAMP:

    yyyy-mm-dd hh:mm:ss[.nnnnnn]
    yyyy-mm-dd-hh.mm.ss[.nnnnnn]

The first of the two formats above is the java.sql.Timestamp format.
The year must always have four digits. Months, days, and hours may have one or two digits. Minutes and seconds must have two digits. Nanoseconds, if present, may have between one and six digits.
Derby also accepts strings in the locale specific datetime format, using the locale of the database server. If there is an ambiguity, the built-in formats above take precedence.
Examples

    VALUES '1960-01-01 23:03:20'
    VALUES TIMESTAMP('1962-09-23 03:23:34.234')
    VALUES TIMESTAMP('1960-01-01 23:03:20')

VARCHAR data type
VARCHAR provides for variable-length storage of strings.
Syntax

    { VARCHAR | CHAR VARYING | CHARACTER VARYING }(length)

length is an unsigned integer constant, and it must not be greater than the constraint of the integer used to specify the length, the value java.lang.Integer.MAX_VALUE.
The maximum length for a VARCHAR string is 32,672 characters.
Corresponding compile-time Java type
java.lang.String
JDBC metadata type (java.sql.Types)
VARCHAR
Derby does not pad a VARCHAR value whose length is less than specified. Derby truncates spaces from a string value when a length greater than the VARCHAR expected is provided. Characters other than spaces are not truncated, and instead cause an exception to be raised. When comparison boolean operators are applied to VARCHARs, the lengths of the operands are not altered, and spaces at the end of the values are ignored.
When CHARs and VARCHARs are mixed in expressions, the shorter value is padded with spaces to the length of the longer value.
The type of a string constant is CHAR, not VARCHAR.
VARCHAR FOR BIT DATA data type
The VARCHAR FOR BIT DATA type allows you to store binary strings less than or equal to a specified length. It is useful for unstructured data where character strings are not appropriate (e.g., images).
Syntax

    { VARCHAR | CHAR VARYING | CHARACTER VARYING } (length) FOR BIT DATA

length is an unsigned integer literal designating the length in bytes.
Unlike the case for the CHAR FOR BIT DATA type, there is no default length for a VARCHAR FOR BIT DATA type. The maximum size of the length value is 32,672 bytes.
JDBC metadata type (java.sql.Types)
VARBINARY
VARCHAR FOR BIT DATA stores variable-length byte strings. Unlike CHAR FOR BIT DATA values, VARCHAR FOR BIT DATA values are not padded out to the target length.
An operation on a VARCHAR FOR BIT DATA and a CHAR FOR BIT DATA value (e.g., a concatenation) yields a VARCHAR FOR BIT DATA value.
The type of a byte literal is always a VARCHAR FOR BIT DATA, not a CHAR FOR BIT DATA.
XML data type
The XML data type is used for Extensible Markup Language (XML) documents.
The XML data type is used:

• |  | To store XML documents that conform to the SQL/XML definition of a well-formed XML(DOCUMENT(ANY)) value.
• |  | Transiently for XML(SEQUENCE) values, that might not be well-formed XML(DOCUMENT(ANY)) values.

Note: For an application to retrieve, update, query, or otherwise access an XML data value, the application must have classes for a JAXP parser and for Xalan in the classpath. Derby issues an error if either the parser or Xalan is not found.
Because none of the JDBC-side support for SQL/XML is implemented in Derby, it is not possible to bind directly into an XML value or to retrieve an XML value directly from a result set using JDBC. Instead, you must bind and retrieve the XML data as Java strings or character streams by explicitly specifying the appropriate XML operators, XMLPARSE and XMLSERIALIZE, as part of your SQL queries.
Syntax

    XML

Corresponding compile-time Java type
None
The Java type for XML values is java.sql.SQLXML. However, the java.sql.SQLXML type is not supported by Derby.
JDBC metadata type (java.sql.Types)
None
The metadata type for XML values is SQLXML. However, the SQLXML type is not supported by Derby.
To retrieve XML values from a Derby database using JDBC, use the XMLSERIALIZE operator in the SQL query. For example:

    SELECT XMLSERIALIZE (xcol as CLOB) FROM myXmlTable

Then retrieve the XML value by using the getXXX method that corresponds to the target serialization type, in this example CLOB data types.
To store an XML value into a Derby database using JDBC, use the XMLPARSE operator in the SQL statement. For example:

    INSERT INTO myXmlTable(xcol) VALUES XMLPARSE(
        DOCUMENT CAST (? AS CLOB) PRESERVE WHITESPACE)

Then use any of the setXXX methods that are compatible with String types, in this example use the PreparedStatement.setString or PreparedStatement.setCharacterStream method calls to bind the operator.
SQL reserved words
This section lists all the Derby reserved words, including those in the SQL-92 standard. Derby will return an error if you use any of these keywords as an identifier name unless you surround the identifier name with quotes ("). See Rules for SQL92 identifiers.

|  | ADD
|  | ALL
|  | ALLOCATE
|  | ALTER
|  | AND
|  | ANY
|  | ARE
|  | AS
|  | ASC
|  | ASSERTION
|  | AT
|  | AUTHORIZATION
|  | AVG
|  | BEGIN
|  | BETWEEN
|  | BIGINT
|  | BIT
|  | BOOLEAN
|  | BOTH
|  | BY
|  | CALL
|  | CASCADE
|  | CASCADED
|  | CASE
|  | CAST
|  | CHAR
|  | CHARACTER
|  | CHECK
|  | CLOSE
|  | COALESCE
|  | COLLATE
|  | COLLATION
|  | COLUMN
|  | COMMIT
|  | CONNECT
|  | CONNECTION
|  | CONSTRAINT
|  | CONSTRAINTS
|  | CONTINUE
|  | CONVERT
|  | CORRESPONDING
|  | CREATE
|  | CURRENT
|  | CURRENT_DATE
|  | CURRENT_TIME
|  | CURRENT_TIMESTAMP
|  | CURRENT_USER
|  | CURSOR
|  | DEALLOCATE
|  | DEC
|  | DECIMAL
|  | DECLARE
|  | DEFAULT
|  | DEFERRABLE
|  | DEFERRED
|  | DELETE
|  | DESC
|  | DESCRIBE
|  | DIAGNOSTICS
|  | DISCONNECT
|  | DISTINCT
|  | DOUBLE
|  | DROP
|  | ELSE
|  | END
|  | END-EXEC
|  | ESCAPE
|  | EXCEPT
|  | EXCEPTION
|  | EXEC
|  | EXECUTE
|  | EXISTS
|  | EXPLAIN
|  | EXTERNAL
|  | FALSE
|  | FETCH
|  | FIRST
|  | FLOAT
|  | FOR
|  | FOREIGN
|  | FOUND
|  | FROM
|  | FULL
|  | FUNCTION
|  | GET
|  | GETCURRENTCONNECTION
|  | GLOBAL
|  | GO
|  | GOTO
|  | GRANT
|  | GROUP
|  | HAVING
|  | HOUR
|  | IDENTITY
|  | IMMEDIATE
|  | IN
|  | INDICATOR
|  | INITIALLY
|  | INNER
|  | INOUT
|  | INPUT
|  | INSENSITIVE
|  | INSERT
|  | INT
|  | INTEGER
|  | INTERSECT
|  | INTO
|  | IS
|  | ISOLATION
|  | JOIN
|  | KEY
|  | LAST
|  | LEFT
|  | LIKE
|  | LOWER
|  | LTRIM
|  | MATCH
|  | MAX
|  | MIN
|  | MINUTE
|  | NATIONAL
|  | NATURAL
|  | NCHAR
|  | NVARCHAR
|  | NEXT
|  | NO
|  | NOT
|  | NULL
|  | NULLIF
|  | NUMERIC
|  | OF
|  | ON
|  | ONLY
|  | OPEN
|  | OPTION
|  | OR
|  | ORDER
|  | OUTER
|  | OUTPUT
|  | OVERLAPS
|  | PAD
|  | PARTIAL
|  | PREPARE
|  | PRESERVE
|  | PRIMARY
|  | PRIOR
|  | PRIVILEGES
|  | PROCEDURE
|  | PUBLIC
|  | READ
|  | REAL
|  | REFERENCES
|  | RELATIVE
|  | RESTRICT
|  | REVOKE
|  | RIGHT
|  | ROLLBACK
|  | ROWS
|  | RTRIM
|  | SCHEMA
|  | SCROLL
|  | SECOND
|  | SELECT
|  | SESSION_USER
|  | SET
|  | SMALLINT
|  | SOME
|  | SPACE
|  | SQL
|  | SQLCODE
|  | SQLERROR
|  | SQLSTATE
|  | SUBSTR
|  | SUBSTRING
|  | SUM
|  | SYSTEM_USER
|  | TABLE
|  | TEMPORARY
|  | TIMEZONE_HOUR
|  | TIMEZONE_MINUTE
|  | TO
|  | TRANSACTION
|  | TRANSLATE
|  | TRANSLATION
|  | TRIM
|  | TRUE
|  | UNION
|  | UNIQUE
|  | UNKNOWN
|  | UPDATE
|  | UPPER
|  | USER
|  | USING
|  | VALUES
|  | VARCHAR
|  | VARYING
|  | VIEW
|  | WHENEVER
|  | WHERE
|  | WITH
|  | WORK
|  | WRITE
|  | XML
|  | XMLEXISTS
|  | XMLPARSE
|  | XMLQUERY
|  | XMLSERIALIZE
|  | YEAR

Derby support for SQL-92 features
There are four levels of SQL-92 support:

• |  | SQL92E Entry
• |  | SQL92T Transitional, a level defined by NIST in a publication called FIPS 127-2
• |  | SQL92I Intermediate
• |  | SQL92F Full

Basic data types
The following table shows Derby support for the SQL-92 basic data types.
Table 13. Support for SQL-92 Features: Basic data types

Feature | Source | Derby
SMALLINT | SQL92E | Yes
INTEGER | SQL92E | Yes
DECIMAL(p,s) | SQL92E | Yes
NUMERIC(p,s) | SQL92E | Yes
REAL | SQL92E | Yes
FLOAT(p) | SQL92E | Yes
DOUBLE PRECISION | SQL92E | Yes
CHAR(n) | SQL92E | Yes

Basic math operations
Table 14. Support for SQL-92 Features: Basic math operations

Feature | Source | Derby
+, *, -, /, unary +, unary - | SQL92E | Yes

Basic comparisons
Table 15. Support for SQL-92 Features: Basic comparisons

Feature | Source | Derby
<, >, <= ,>=, <>, = | SQL92E | Yes

Basic predicates
Table 16. Support for SQL-92 Features: Basic predicates

Feature | Source | Derby
BETWEEN, LIKE, NULL | SQL92E | Yes

Quantified predicates
Table 17. Support for SQL-92 Features: Quantified predicates

Feature | Source | Derby
IN, ALL/SOME, EXISTS | SQL92E | Yes

Schema definition
Table 18. Support for SQL-92 Features: schema definition

Feature | Source | Derby
Tables | SQL92E | Yes
Views | SQL92E | Yes
Privileges | SQL92E | Yes

Column attributes
Table 19. Support for SQL-92 Features: column attributes

Feature | Source | Derby
Default values | SQL92E | Yes
Nullability | SQL92E | Yes

Constraints (non-deferrable)
Table 20. Support for SQL-92 Features: constraints (non-deferrable)

Feature | Source | Derby
NOT NULL | SQL92E | Yes (not stored in SYSCONSTRAINTS)
UNIQUE/PRIMARY KEY | SQL92E | Yes
FOREIGN KEY | SQL92E | Yes
CHECK | SQL92E | Yes
View WITH CHECK OPTION | SQL92E | No, views cannot be updated

Cursors
Table 21. Support for SQL-92 Features: Cursors

Feature | Source | Derby
DECLARE, OPEN, FETCH, CLOSE | SQL92E | Yes, by using JDBC method calls
UPDATE, DELETE CURRENT | SQL92E | Yes

Dynamic SQL 1
Table 22. Support for SQL-92 Features: Dynamic SQL 1

Feature | Source | Derby
ALLOCATE / DEALLOCATE / GET / SET DESCRIPTOR | SQL92T | Yes, by using JDBC method calls
PREPARE / EXECUTE / EXECUTE IMMEDIATE | SQL92T | Yes, by using JDBC method calls
DECLARE, OPEN, FETCH, CLOSE, UPDATE, DELETE dynamic cursor | SQL92T | Yes, by using JDBC method calls
DESCRIBE output | SQL92T | Yes, by using JDBC method calls

Basic information schema
Table 23. Support for SQL-92 Features: Basic information schema

Feature | Source | Derby
TABLES | SQL92T | SYS.SYSTABLES, SYS.SYSVIEWS, SYS.SYSCOLUMNS
VIEWS | SQL92T | SYS.SYSTABLES, SYS.SYSVIEWS, SYS.SYSCOLUMNS
COLUMNS | SQL92T | SYS.SYSTABLES, SYS.SYSVIEWS, SYS.SYSCOLUMNS

Basic schema manipulation
Table 24. Support for SQL-92 Features: Basic schema manipulation

Feature | Source | Derby
CREATE / DROP TABLE | SQL92T | Yes
CREATE / DROP VIEW | SQL92T | Yes
GRANT / REVOKE | SQL92T | Yes
ALTER TABLE ADD COLUMN | SQL92T | Yes
ALTER TABLE DROP COLUMN | SQL92T | Yes

Joined table
Table 25. Support for SQL-92 Features: Joined table

Feature | Source | Derby
INNER JOIN | SQL92T | Yes
natural join | SQL92T | No
LEFT, RIGHT OUTER JOIN | SQL92T | Yes
join condition | SQL92T | Yes
named columns join | SQL92T | Yes

Date and time data types
Table 26. Support for SQL-92 Features: Date and time data types

Feature | Source | Derby
simple DATE, TIME, TIMESTAMP, INTERVAL | SQL92T | Yes, not INTERVAL
datetime constants | SQL92T | Yes
datetime math | SQL92T | Yes, with Java methods
datetime comparisons | SQL92T | Yes
predicates: OVERLAPS | SQL92T | Yes, with Java methods

VARCHAR data type
Table 27. Support for SQL-92 Features: VARCHAR

Feature | Source | Derby
LENGTH | SQL92T | Yes
concatenation (||) | SQL92T | Yes

Transaction isolation
Table 28. Support for SQL-92 Features: Transaction isolation

Feature | Source | Derby
READ WRITE / READ ONLY | SQL92T | By using JDBC, database properties, and storage media
RU, RC, RR, SER | SQL92T | Yes

Multiple schemas per user
Table 29. Support for SQL-92 Features: Multiple schemas per user

Feature | Source | Derby
SCHEMATA view | SQL92T | SYS.SYSSCHEMAS

Privilege tables
Table 30. Support for SQL-92 Features: Privilege tables

Feature | Source | Derby
TABLE_PRIVILEGES | SQL92T | No
COLUMNS_PRIVILEGES | SQL92T | No
USAGE_PRIVILEGES | SQL92T | No

Table operations
Table 31. Support for SQL-92 Features: Table operations

Feature | Source | Derby
UNION relaxations | SQL92I | Yes
EXCEPT | SQL92I | Yes
INTERSECT | SQL92I | Yes
CORRESPONDING | SQL92I | No

Schema definition statement
Table 32. Support for SQL-92 Features: Schema definition statement

Feature | Source | Derby
CREATE SCHEMA | SQL92I | Partial support

User authorization
Table 33. Support for SQL-92 Features: User authorization

Feature | Source | Derby
SET SESSION AUTHORIZATION | SQL92I | Use SET SCHEMA
CURRENT_USER | SQL92I | Yes
SESSION_USER | SQL92I | Yes
SYSTEM_USER | SQL92I | No

Constraint tables
Table 34. Support for SQL-92 Features: Constraint tables

Feature | Source | Derby
TABLE CONSTRAINTS | SQL92I | SYS.SYSCONSTRAINTS
REFERENTIAL CONSTRAINTS | SQL92I | SYS.SYSFOREIGNKEYS
CHECK CONSTRAINTS | SQL92I | SYS.SYSCHECKS

Documentation schema
Table 35. Support for SQL-92 Features: Documentation schema

Feature | Source | Derby
SQL_FEATURES | SQL92I/FIPS 127-2 | Use JDBC DatabaseMetaData
SQL_SIZING | SQL92I/FIPS 127-2 | Use JDBC DatabaseMetaData

Full DATETIME
Table 36. Support for SQL-92 Features: Full DATETIME

Feature | Source | Derby
precision for TIME and TIMESTAMP | SQL92F | Yes

Full character functions
Table 37. Support for SQL-92 Features: Full character functions

Feature | Source | Derby
POSITION expression | SQL92F | Use Java methods or LOCATE
UPPER/LOWER functions | SQL92F | Yes

Miscellaneous features
Table 38. Support for SQL-92 Features: Miscellaneous

Feature | Source | Derby
Delimited identifiers | SQL92E | Yes
Correlated subqueries | SQL92E | Yes
Insert, Update, Delete statements | SQL92E | Yes
Joins | SQL92E | Yes
Where qualifications | SQL92E | Yes
Group by | SQL92E | Yes
Having | SQL92E | Yes
Aggregate functions | SQL92E | Yes
Order by | SQL92E | Yes
Select expressions | SQL92E | Yes
Select * | SQL92E | Yes
SQLCODE | SQL92E | No, deprecated in SQL-92
SQLSTATE | SQL92E | Yes
UNION, INTERSECT, and EXCEPT in views | SQL92T | Yes
Implicit numeric casting | SQL92T | Yes
Implicit character casting | SQL92T | Yes
Get diagnostics | SQL92T | Use JDBC SQLExceptions
Grouped operations | SQL92T | Yes
Qualified * in select list | SQL92T | Yes
Lowercase identifiers | SQL92T | Yes
nullable PRIMARY KEYs | SQL92T | No
Multiple module support | SQL92T | No (not required and not part of JDBC)
Referential delete actions | SQL92T | CASCADE, SET NULL, RESTRICT, and NO ACTION
CAST functions | SQL92T | Yes
INSERT expressions | SQL92T | Yes
Explicit defaults | SQL92T | Yes
Keyword relaxations | SQL92T | Yes
Domain definition | SQL92I | No
CASE expression | SQL92I | Partial support
Compound character string constants | SQL92I | Use concatenation
LIKE enhancements | SQL92I | Yes
UNIQUE predicate | SQL92I | No
Usage tables | SQL92I | SYS.SYSDEPENDS
Intermediate information schema | SQL92I | Use JDBC DatabaseMetaData and Derby system tables
Subprogram support | SQL92I | Not relevant to JDBC, which is much richer
Intermediate SQL Flagging | SQL92I | No
Schema manipulation | SQL92I | Yes
Long identifiers | SQL92I | Yes
Full outer join | SQL92I | No
Time zone specification | SQL92I | No
Scrolled cursors | SQL92I | Partial support (scrollable insensitive result sets through JDBC 2.0)
Intermediate set function support | SQL92I | Partial support
Character set definition | SQL92I | Support for Java locales
Named character sets | SQL92I | Support for Java locales
Scalar subquery values | SQL92I | Yes
Expanded null predicate | SQL92I | Yes
Constraint management | SQL92I | Yes (ADD/DROP CONSTRAINT)
FOR BIT DATA types | SQL92F | Yes
Assertion constraints | SQL92F | No
Temporary tables | SQL92F | Partial support, with DECLARE GLOBAL TEMPORARY TABLE
Full dynamic SQL | SQL92F | No
Full value expressions | SQL92F | Yes
Truth value tests | SQL92F | Yes
Derived tables in FROM | SQL92F | Yes
Trailing underscore | SQL92F | Yes
Indicator data types | SQL92F | Not relevant to JDBC
Referential name order | SQL92F | No
Full SQL Flagging | SQL92F | No
Row and table constructors | SQL92F | Yes
Catalog name qualifiers | SQL92F | No
Simple tables | SQL92F | No
Subqueries in CHECK | SQL92F | No, but can with Java methods
Union join | SQL92F | No
Collation and translation | SQL92F | Java locales supported
Referential update actions | SQL92F | RESTRICT and NO ACTION. Can do others with triggers.
ALTER domain | SQL92F | nNo
INSERT column privileges | SQL92F | No
Referential MATCH types | SQL92F | No
View CHECK enhancements | SQL92F | No, views cannot be updated
Session management | SQL92F | Use JDBC
Connection management | SQL92F | Use JDBC
Self-referencing operations | SQL92F | Yes
Insensitive cursors | SQL92F | Yes through JDBC 2.0
Full set function | SQL92F | Partial support
Catalog flagging | SQL92F | No
Local table references | SQL92F | No
Full cursor update | SQL92F | No

Derby system tables
Derby includes system tables.
You can query system tables, but you cannot alter them.
All of the above system tables reside in the SYS schema. Because this is not the default schema, qualify all queries accessing the system tables with the SYS schema name.
The recommended way to get more information about these tables is to use an instance of the Java interface java.sql.DatabaseMetaData.
SYSALIASES system table
Describes the procedures and functions in the database.

Column Name | Type | Length | Nullability | Contents
ALIASID | CHAR | 36 | false | unique identifier for the alias
ALIAS | VARCHAR | 128 | false | alias
SCHEMAID | CHAR | 36 | true | reserved for future use
JAVACLASSNAME | LONGVARCHAR | 255 | false | the Java class name
ALIASTYPE | CHAR | 1 | false | 'F' (function)'P' (procedure)
NAMESPACE | CHAR | 1 | false | 'F' (function)'P' (procedure)
SYSTEMALIAS | BOOLEAN | ' | false | true (system supplied or built-in alias) false (alias created by a user)
ALIASINFO |
    org.apache.derby.
    catalog.AliasInfo:
This class is not part of the public API | ' | true | A Java interface that encapsulates the additional information that is specific to an alias
SPECIFICNAME | VARCHAR | 128 | false | system-generated identifier

SYSCHECKS system table
Describes the check constraints within the current database.

Column Name | Type | Length | Nullability | Contents
CONSTRAINTID | CHAR | 36 | false | unique identifier for the constraint
CHECKDEFINITION | LONG VARCHAR | ' | false | text of check constraint definition
REFERENCEDCOLUMNS | org.apache.derby.catalog. ReferencedColumns: This class is not part of the public API. | ' | false | description of the columns referenced by the check constraint

SYSCOLPERMS system table
The SYSCOLPERMS table stores the column permissions that have been granted but not revoked.
All of the permissions for one (GRANTEE, TABLEID, TYPE, GRANTOR) combination are specified in a single row in the SYSCOLPERMS table. The keys for the SYSCOLPERMS table are:

• |  | Primary key (GRANTEE, TABLEID, TYPE, GRANTOR)
• |  | Unique key (COLPERMSID)
• |  | Foreign key (TABLEID references SYS.SYSTABLES)

Column Name | Type | Length | Nullability | Contents
COLPERMSID | CHAR | 36 | false | Used by the dependency manager to track the dependency of a view, trigger, or constraint on the column level permissions.
GRANTEE | VARCHAR | 30 | false | The authorization ID of the user to whom the privilege was granted.
GRANTOR | VARCHAR | 30 | false | The authorization ID of the user who granted the privilege. Privileges can be granted only by the object owner.
TABLEID | CHAR | 36 | false | The unique identifier for the table on which the permissions have been granted.
TYPE | CHAR | 1 | false | The type of column permission:
    S for SELECT
    U for UPDATE
    R for REFERENCES
COLUMNS | org.apache.derby.iapi.services.io.FormatableBitSet | ' | false | A list of columns to which the privilege applies. This class is not part of the public API.

SYSCOLUMNS system table
Describes the columns within all tables in the current database:

Column Name | Type | Length | Nullable | Contents
REFERENCEID | CHAR | 36 | false | Identifier for table (join with SYSTABLES.TABLEID)
COLUMNNAME | CHAR | 128 | false | column or parameter name
COLUMNNUMBER | INT | 4 | false | the position of the column within the table
COLUMNDATATYPE | org.apache.derby.catalog. TypeDescriptor This class is not part of the public API. | ' | false | system type that describes precision, length, scale, nullability, type name, and storage type of data
COLUMNDEFAULT | java.io.Serializable | ' | true | for tables, describes default value of the column. The toString() method on the object stored in the table returns the text of the default value as specified in the CREATE TABLE or ALTER TABLE statement.
COLUMNDEFAULTID | CHAR | 36 | true | unique identifier for the default value
AUTOINCREMENT COLUMNVALUE | BIGINT | ' | true | what the next value for column will be, if the column is an identity column
AUTOINCREMENT COLUMNSTART | BIGINT | ' | true | initial value of column (if specified), if it is an identity column
AUTOINCREMENT COLUMNINC | BIGINT | ' | true | amount column value is automatically incremented (if specified), if the column is an identity column

SYSCONGLOMERATES system table
Describes the conglomerates within the current database. A conglomerate is a unit of storage and is either a table or an index.

Column Name | Type | Length | Nullable | Contents
SCHEMAID | CHAR | 36 | false | schema id for the conglomerate
TABLEID | CHAR | 36 | false | identifier for table (join with SYSTABLES.TABLEID)
CONGLOMERATENUMBER | BIGINT | 8 | false | conglomerate id for the conglomerate (heap or index)
CONGLOMERATENAME | VARCHAR | 128 | true | index name, if conglomerate is an index, otherwise the table ID
ISINDEX | BOOLEAN | 1 | false | whether or not conglomerate is an index
DESCRIPTOR |
    org.apache.derby.
    catalog.IndexDescriptor:
This class is not part of the public API. | ' | true | system type describing the index
ISCONSTRAINT | BOOLEAN | 1 | true | whether or not conglomerate is a system-generated index enforcing a constraint
CONGLOMERATEID | CHAR | 36 | false | unique identifier for the conglomerate

SYSCONSTRAINTS system table
Describes the information common to all types of constraints within the current database (currently, this includes primary key, unique, foreign key, and check constraints).

Column Name | Type | Length | Nullable | Contents
CONSTRAINTID | CHAR | 36 | false | unique identifier for constraint
TABLEID | CHAR | 36 | false | identifier for table (join with SYSTABLES.TABLEID)
CONSTRAINTNAME | VARCHAR | 128 | false | constraint name (internally generated if not specified by user)
TYPE | CHAR | 1 | false | P (primary key), U (unique), C (check), or F (foreign key)
SCHEMAID | CHAR | 36 | false | identifier for schema that the constraint belongs to (join with SYSSCHEMAS.SCHEMAID)
STATE | CHAR | 1 | false | E for enabled, D for disabled
REFERENCECOUNT | INTEGER | 1 | false | the count of the number of foreign key constraints that reference this constraint; this number can be greater than zero only for PRIMARY KEY and UNIQUE constraints

SYSDEPENDS system table
The SYSDEPENDS table stores the dependency relationships between persistent objects in the database.
Persistent objects can be dependents or providers. Dependents are objects that depend on other objects. Providers are objects that other objects depend on.

• |  | Dependents are views, constraints, or triggers.
• |  | Providers are tables, conglomerates, constraints, or privileges.

Column Name | Type | Length | Nullable | Contents
DEPENDENTID | CHAR | 36 | false | A unique identifier for the dependent.
DEPENDENTFINDER | org.apache.derby.catalog. DependableFinder: This class is not part of the public API. | 1 | false | A system type that describes the view, constraint, or trigger that is the dependent.
PROVIDERID | CHAR | 36 | false | A unique identifier for the provider.
PROVIDERFINDER | org.apache.derby.catalog. DependableFinder This class is not part of the public API. | 1 | false | A system type that describes the table, conglomerate, constraint, and privilege that is the provider

SYSFILES system table
Describes jar files stored in the database.

Column Name | Type | Length | Nullability | Contents
FILEID | CHAR | 36 | false | unique identifier for the jar file
SCHEMAID | CHAR | 36 | false | ID of the jar file's schema (join with SYSSCHEMAS. SCHEMAID)
FILENAME | VARCHAR | 128 | false | SQL name of the jar file
GENERATIONID | BIGINT | ' | false | Generation number for the file. When jar files are replaced, their generation identifiers are changed.

SYSFOREIGNKEYS system table
Describes the information specific to foreign key constraints in the current database.
Derby generates a backing index for each foreign key constraint; the name of this index is the same as SYSFOREIGNKEYS.CONGLOMERATEID.

Column Name | Type | Length | Nullability | Contents
CONSTRAINTID | CHAR | 36 | false | unique identifier for the foreign key constraint (join with SYSCONSTRAINTS. CONSTRAINTID)
CONGLOMERATEID | CHAR | 36 | false | unique identifier for index backing up the foreign key constraint (join with SYSCONGLOMERATES. CONGLOMERATEID)
KEYCONSTRAINTID | CHAR | 36 | false | unique identifier for the primary key or unique constraint referenced by this foreign key (SYSKEYS.CONSTRAINTID or SYSCONSTRAINTS. CONSTRAINTID)
DELETERULE | CHAR | 1 | false | R for NO ACTION (default), S for RESTRICT, C for CASCADE, U for SET NULL
UPDATERULE | CHAR | 1 | false | R for NO ACTION(default), S for restrict

SYSKEYS system table
Describes the specific information for primary key and unique constraints within the current database. Derby generates an index on the table to back up each such constraint. The index name is the same as SYSKEYS.CONGLOMERATEID.

Column Name | Type | Length | Nullable | Contents
CONSTRAINTID | CHAR | 36 | false | unique identifier for constraint
CONGLOMERATEID | CHAR | 36 | false | unique identifier for backing index

SYSROUTINEPERMS system table
The SYSROUTINEPERMS table stores the permissions that have been granted to routines.
Each routine EXECUTE permission is specified in a row in the SYSROUTINEPERMS table. The keys for the SYSROUTINEPERMS table are:

• |  | Primary key (GRANTEE, ALIASID, GRANTOR)
• |  | Unique key (ROUTINEPERMSID)
• |  | Foreign key (ALIASID references SYS.SYSALIASES)

The column information for the SYSTABLEPERMS table is listed in the following table:

Column Name | Type | Length | Nullability | Contents
ROUTINEPERMSID | CHAR | 36 | false | Used by the dependency manager to track the dependency of a view, trigger, or constraint on the routine level permissions.
GRANTEE | VARCHAR | 30 | false | The authorization ID of the user to whom the privilege is granted.
GRANTOR | VARCHAR | 30 | false | The authorization ID of the user who granted the privilege. Privileges can be granted only by the object owner.
ALIASID | CHAR | 36 | false | The ID of the object of the required permission. If PERMTYPE='E' the ALIASID is a reference to the SYS.SYSALIASES table. Otherwise the ALIASID is a reference to the SYS.SYSTABLES table.
GRANTOPTION | CHAR | 1 | false | Specifies if the GRANTEE is the owner of the routine. Valid values are Y and N.

SYSSCHEMAS system table
Describes the schemas within the current database.

Column Name | Type | Length | Nullability | Contents
SCHEMAID | CHAR | 36 | false | unique identifier for the schema
SCHEMANAME | VARCHAR | 128 | false | schema name
AUTHORIZATIONID | VARCHAR | 128 | false | the authorization identifier of the owner of the schema

SYSSTATISTICS system table
Describes the schemas within the current database.

Column Name | Type | Length | Nullability | Contents
STATID | CHAR | 36 | false | unique identifier for the statistic
REFERENCEID | CHAR | 36 | false | the conglomerate for which the statistic was created (join with SYSCONGLOMERATES. CONGLOMERATEID)
TABLEID | CHAR | 36 | false | the table for which the information is collected
CREATIONTIMESTAMP | TIMESTAMP | ' | false | time when this statistic was created or updated
TYPE | CHAR | 1 | false | type of statistics
VALID | BOOLEAN | ' | false | whether the statistic is still valid
COLCOUNT | INTEGER | ' | false | number of columns in the statistic
STATISTICS |
    org.apache.
    derby.catalog.
    Statistics:
This class is not part of the public API. | ' | true | statistics information

SYSSTATEMENTS system table
Contains one row per stored prepared statement.

Column Name | Type | Length | Nullability | Contents
STMTID | CHAR | 36 | false | unique identifier for the statement
STMTNAME | VARCHAR | 128 | false | name of the statement
SCHEMAID | CHAR | 36 | false | the schema in which the statement resides
TYPE | CHAR | 1 | false | always 'S'
VALID | BOOLEAN | ' | false | TRUE if valid, FALSE if invalid
TEXT | LONG VARCHAR | ' | false | text of the statement
LASTCOMPILED | TIMESTAMP | ' | true | time that the statement was compiled
COMPILATION SCHEMAID | CHAR | 36 | false | id of the schema containing the statement
USINGTEXT | LONG VARCHAR | ' | true | text of the USING clause of the CREATE STATEMENT and ALTER STATEMENT statements

SYSTABLEPERMS system table
The SYSTABLEPERMS table stores the table permissions that have been granted but not revoked.
All of the permissions for one (GRANTEE, TABLEID, GRANTOR) combination are specified in a single row in the SYSTABLEPERMS table. The keys for the SYSTABLEPERMS table are:

• |  | Primary key (GRANTEE, TABLEID, GRANTOR)
• |  | Unique key (TABLEPERMSID)
• |  | Foreign key (TABLEID references SYS.SYSTABLES)

The column information for the SYSTABLEPERMS table is listed in the following table:

Column Name | Type | Length | Nullability | Contents
TABLEPERMSID | CHAR | 36 | false | Used by the dependency manager to track the dependency of a view, trigger, or constraint on the table level permissions.
GRANTEE | VARCHAR | 30 | false | The authorization ID of the user to whom the privilege is granted.
GRANTOR | VARCHAR | 30 | false | The authorization ID of the user who granted the privilege. Privileges can be granted only by the object owner.
TABLEID | CHAR | 36 | false | The unique identifier for the table on which the permissions have been granted.
SELECTPRIV | CHAR | 1 | false | Specifies if the SELECT permission is granted. Valid values are Y and N.
DELETEPRIV | CHAR | 1 | false | Specifies if the DELETE permission is granted. Valid values are Y and N.
INSERTPRIV | CHAR | 1 | false | Specifies if the INSERT permission is granted. Valid values are Y and N.
UPDATEPRIV | CHAR | 1 | false | Specifies if the UPDATE permission is granted. Valid values are Y and N.
REFERENCEPRIV | CHAR | 1 | false | Specifies if the REFERENCE permission is granted. Valid values are Y and N.
TRIGGERPRIV | CHAR | 1 | false | Specifies if the TRIGGER permission is granted. Valid values are Y and N.

SYSTABLES system table
Describes the tables and views within the current database.

Column Name | Type | Length | Nullable | Contents
TABLEID | CHAR | 36 | false | unique identifier for table or view
TABLENAME | VARCHAR | 128 | false | table or view name
TABLETYPE | CHAR | 1 | false | 'S' (system table), 'T' (user table), or 'V' (view)
SCHEMAID | CHAR | 36 | false | schema id for the table or view
LOCK GRANULARITY | CHAR | 1 | false | Indicates the lock granularity for the table 'T' (table level locking) 'R' (row level locking, the default)

SYSTRIGGERS system table
Describes the database's triggers.

Column Name | Type | Length | Nullability | Contents
TRIGGERID | CHAR | 36 | false | unique identifier for the trigger
TRIGGERNAME | VARCHAR | 128 | false | name of the trigger
SCHEMAID | CHAR | 36 | false | id of the trigger's schema (join with SYSSCHEMAS. SCHEMAID)
CREATIONTIMESTAMP | TIMESTAMP | ' | false | time the trigger was created
EVENT | CHAR | 1 | false | 'U' for update, 'D' for delete, 'I' for insert
FIRINGTIME | CHAR | 1 | false | 'B' for before 'A' for after
TYPE | CHAR | 1 | false | 'R' for row, 'S' for statement
STATE | CHAR | 1 | false | 'E' for enabled, 'D' for disabled
TABLEID | CHAR | 36 | false | id of the table on which the trigger is defined
WHENSTMTID | CHAR | 36 | true | used only if there is a WHEN clause (not yet supported)
ACTIONSTMTID | CHAR | 36 | true | id of the stored prepared statement for the triggered-SQL-statement (join with SYSSTATEMENTS. STMTID)
REFERENCEDCOLUMNS | org.apache.derby.catalog. ReferencedColumns: This class is not part of the public API. | ' | true | descriptor of the columns referenced by UPDATE triggers
TRIGGERDEFINITION | LONG VARCHAR | ' | true | text of the action SQL statement
REFERENCINGOLD | BOOLEAN | ' | true | whether or not the OLDREFERENCINGNAME, if non-null, refers to the OLD row or table
REFERENCINGNEW | BOOLEAN | ' | true | whether or not the NEWREFERENCINGNAME, if non-null, refers to the NEW row or table
OLDREFERENCINGNAME | VARCHAR | 128 | true | pseudoname as set using the REFERENCING OLD AS clause
NEWREFERENCINGNAME | VARCHAR | 128 | true | pseudoname as set using the REFERENCING NEW AS clause

Any SQL text that is part of a triggered-SQL-statement is compiled and stored in SYSSTATEMENTS. ACTIONSTMTID and WHENSTMTID are foreign keys that reference SYSSTATEMENTS.STMTID. The statements for a trigger are always in the same schema as the trigger.
SYSVIEWS system table
Describes the view definitions within the current database.

Column Name | Type | Length | Nullability | Contents
TABLEID | CHAR | 36 | false | unique identifier for the view (called TABLEID since it is joined with column of that name in SYSTABLES)
VIEWDEFINITION | LONG VARCHAR | ' | false | text of view definition
CHECKOPTION | CHAR | 1 | false | 'N' (check option not supported yet)
COMPILATION SCHEMAID | CHAR | 36 | false | id of the schema containing the view

Derby exception messages and SQL states
The JDBC driver returns SQLExceptions for all errors from Derby. If the exception originated in a user type but is not itself an SQLException, it is wrapped in an SQLException. Derby-specific SQLExceptions use SQLState class codes starting with X. Standard SQLState values are returned for exceptions where appropriate.
Unimplemented aspects of the JDBC driver return a SQLException with a SQLState starting with 0A. If your application runs on JDK 1.6 or higher, then the exception class is java.sql.SQLFeatureNotSupportedException. These unimplemented parts are for features not supported by Derby.
Derby supplies values for the message and SQLState fields. In addition, Derby sometimes returns multiple SQLExceptions using the nextException chain. The first exception is always the most severe exception, with SQL-92 Standard exceptions preceding those that are specific to Derby.
For information on processing SQLExceptions, see the Java DB Developer's Guide.
SQL error messages and exceptions
The following tables list SQLStates for exceptions. Exceptions that begin with an X are specific to Derby.
Table 39. Class 01: Warning

SQLSTATE | Message Text
01001 | An attempt to update or delete an already deleted row was made: No row was updated or deleted.
01003 | Null values were eliminated from the argument of a column function.
01006 | Privilege not revoked from user <authorizationID>.
0100E | XX Attempt to return too many result sets.
01500 | The constraint <constraintName> on table <tableName> has been dropped.
01501 | The view <viewName> has been dropped.
01502 | The trigger <triggerName> on table <tableName> has been dropped.
01503 | The column <columnName> on table <tableName> has been modified by adding a not null constraint.
01504 | The new index is a duplicate of an existing index: <indexName>.
01505 | The value <valueName> may be truncated.
01522 | The newly defined synonym '<synonymName>' resolved to the object '<objectName>' which is currently undefined.
01J01 | Database '<databaseName>' not created, connection made to existing database instead.
01J02 | Scroll sensitive cursors are not currently implemented.
01J04 | The class '<className>' for column '<columnName>' does not implement java.io.Serializable or java.sql.SQLData. Instances must implement one of these interfaces to allow them to be stored.
01J05 | Database upgrade succeeded. The upgraded database is now ready for use. Revalidating stored prepared statements failed. See next exception for details of failure.
01J06 | ResultSet not updatable. Query does not qualify to generate an updatable ResultSet.
01J07 | ResultSetHoldability restricted to ResultSet.CLOSE_CURSORS_AT_COMMIT for a global transaction.
01J08 | Unable to open resultSet type <resultSetType>. ResultSet type <resultSetType> opened.
01J10 | Scroll sensitive result sets are not supported by server; remapping to forward-only cursor
01J12 | Unable to obtain message text from server. See the next exception. The stored procedure SYSIBM.SQLCAMESSAGE is not installed on the server. Please contact your database administrator.
01J13 | Number of rows returned (<number>) is too large to fit in an integer; the value returned will be truncated.
01J14 | SQL authorization is being used without first enabling authentication.

Table 40. Class 07: Dynamic SQL Error

SQLSTATE | Message Text
07000 | At least one parameter to the current statement is uninitialized.
07004 | Parameter <parameterName> is an <procedureName> procedure parameter and must be registered with CallableStatement.registerOutParameter before execution.
07009 | No input parameters.

Table 41. Class 08: Connection Exception

SQLSTATE | Message Text
08000 | Connection closed by unknown interrupt.
08000 | Cannot close a connection with an active transaction. The transaction remains open and the connection was not closed.
08001 | A connection could not be established because the security token is larger than the maximum allowed by the network protocol.
08001 | A connection could not be established because the user id has a length of zero or is larger than the maximum allowed by the network protocol.
08001 | A connection could not be established because the password has a length of zero or is larger than the maximum allowed by the network protocol.
08001 | Required Derby DataSource property <propertyName> not set.
08001 | <error> : Error connecting to server <serverName> on port <portNumber> with message <messageText>.
08001 | SocketException: '<error>'
08001 | Unable to open stream on socket: '<error>'.
08001 | User id length (<number>) is outside the range of 1 to <number>.
08001 | Password length (<value>) is outside the range of 1 to <number>.
08001 | User id can not be null.
08001 | Password can not be null.
08001 | A connection could not be established because the database name '<databaseName>' is larger than the maximum length allowed by the network protocol.
08003 | No current connection.
08003 | getConnection() is not valid on a closed PooledConnection.
08003 | Lob method called after connection was closed
08003 | The underlying physical connection is stale or closed.
08004 | Connection refused : <connectionName>
08004 | Connection authentication failure occurred. Reason: <reasonText>.
08004 | The connection was refused because the database <databaseName> was not found.
08004 | Database connection refused.
08004 | User '<authorizationID>' cannot shut down database '<databaseName>'. Only the database owner can perform this operation.
08004 | User '<authorizationID>' cannot (re)encrypt database '<databaseName>'. Only the database owner can perform this operation.
08004 | User '<authorizationID>' cannot hard upgrade database '<databaseName>'. Only the database owner can perform this operation.
08006 | An error occurred during connect reset and the connection has been terminated. See chained exceptions for details.
08006 | Database '<databaseName>' shutdown.

Table 42. Class 0A: Feature not supported

SQLSTATE | Message Text
0A000 | Feature not implemented: <featureName>.
0A000 | The DRDA command <commandName> is not currently implemented. The connection has been terminated.
0A000 | JDBC method is not yet implemented.
0A000 | JDBC method <methodName> is not supported by the server. Please upgrade the server.
0A000 | resultSetHoldability property <propertyName> not supported
0A000 | cancel() not supported by the server.
0A000 | Security mechanism '<mechanismName>' is not supported.
0A000 | The data type '<datatypeName>' is not supported.

Table 43. Class 21: Cardinality Violation

SQLSTATE | Message Text
21000 | Scalar subquery is only allowed to return a single row.

Table 44. Class 22: Data Exception

SQLSTATE | Message Text
22001 | A truncation error was encountered trying to shrink <value> '<value>' to length <value>.
22003 | The resulting value is outside the range for the data type <datatypeName>.
22003 | Year (<value>) exceeds the maximum '<value>'.
22003 | Decimal may only be up to 31 digits.
22003 | Overflow occurred during numeric data type conversion of '<datatypeName>' to <datatypeName>.
22004 | The length (<number>) exceeds the maximum length for the data type (<datatypeName>).
22005 | Unable to convert a value of type '<typeName>' to type '<typeName>' : the encoding is not supported.
22005 | The required character converter is not available.
22005 | Unicode string cannot convert to Ebcdic string
22005 | Unrecognized JDBC type. Type: <typeName>, columnCount: <value>, columnIndex: <value>.
22005 | Invalid JDBC type for parameter <parameterName>.
22005 | Unrecognized Java SQL type <datatypeName>.
22005 | An attempt was made to get a data value of type '<datatypeName>' from a data value of type '<datatypeName>'.
22007 | The string representation of a datetime value is out of range.
22007 | The syntax of the string representation of a datetime value is incorrect.
22008 | '<argument>' is an invalid argument to the <functionName> function.
2200L | Values assigned to XML columns must be well-formed DOCUMENT nodes.
2200M | Invalid XML DOCUMENT: <parserError>
2200V | Invalid context item for <operatorName> operator; context items must be well-formed DOCUMENT nodes.
2200W | XQuery serialization error: Attempted to serialize one or more top-level Attribute nodes.
22011 | The second or third argument of the SUBSTR function is out of range.
22012 | Attempt to divide by zero.
22013 | Attempt to take the square root of a negative number, '<value>'.
22014 | The start position for LOCATE is invalid; it must be a positive integer. The index to start the search from is '<fromString>'. The string to search for is '<startIndex>'. The string to search from is '<searchString>'.
22015 | Invalid data conversion: requested conversion would result in a loss of precision of <value>
22015 | The '<functionName>' function is not allowed on the following set of types. First operand is of type '<typeName>'. Second operand is of type '<typeName>'. Third operand (start position) is of type '<typeName>'.
22018 | Invalid character string format for type <typeName>.
22019 | Invalid escape sequence, '<sequenceName>'. The escape string must be exactly one character. It cannot be a null or more than one character.
22020 | Invalid trim string, '<string>'. The trim string must be exactly one character or NULL. It cannot be more than one character.
22025 | Escape character must be followed by escape character, '_', or '%'. It cannot be followed by any other character or be at the end of the pattern.
22027 | The built-in TRIM() function only supports a single trim character. The LTRIM() and RTRIM() built-in functions support multiple trim characters.
22028 | The string exceeds the maximum length of <number>.
22501 | An ESCAPE clause of NULL returns undefined results and is not allowed.

Table 45. Class 23: Constraint Violation

SQLSTATE | Message Text
23502 | Column '<columnName>' cannot accept a NULL value.
23503 | <constraintName> on table '<tableName>' caused a violation of foreign key constraint '<value>' for key <keyName>. The statement has been rolled back.
23505 | The statement was aborted because it would have caused a duplicate key value in a unique or primary key constraint or unique index identified by '<value>' defined on '<value>'.
23513 | The check constraint '<tableName>' was violated while performing an INSERT or UPDATE on table '<constraintName>'.

Table 46. Class 24: Invalid Cursor State

SQLSTATE | Message Text
24000 | Invalid cursor state - no current row.
24501 | The identified cursor is not open.

Table 47. Class 25: Invalid Transaction State

SQLSTATE | Message Text
25000 | Invalid transaction state.
25001 | Cannot close a connection while a transaction is still active.
25501 | Unable to set the connection read-only property in an active transaction.
25502 | An SQL data change is not permitted for a read-only connection, user or database.
25503 | DDL is not permitted for a read-only connection, user or database.
25505 | A read-only user or a user in a read-only database is not permitted to disable read-only mode on a connection.

Table 48. Class 28: Invalid Authorization Specification

SQLSTATE | Message Text
28502 | The user name '<authorizationID>' is not valid.

Table 49. Class 2D: Invalid Transaction Termination

SQLSTATE | Message Text
2D521 | setAutoCommit(true) invalid during global transaction.
2D521 | COMMIT or ROLLBACK invalid for application execution environment.

Table 50. Class 38: External Function Exception

SQLSTATE | Message Text
38000 | The exception '<exception>' was thrown while evaluating an expression.
38001 | The external routine is not allowed to execute SQL statements.
38002 | The routine attempted to modify data, but the routine was not defined as MODIFIES SQL DATA.
38004 | The routine attempted to read data, but the routine was not defined as READS SQL DATA.

Table 51. Class 39: External Routine Invocation Exception

SQLSTATE | Message Text
39004 | A NULL value cannot be passed to a method which takes a parameter of primitive type '<type>'.

Table 52. Class 3B: Invalid SAVEPOINT

SQLSTATE | Message Text
3B001 | SAVEPOINT, <savepointName> does not exist or is not active in the current transaction.
3B002 | The maximum number of savepoints has been reached.
3B501 | A SAVEPOINT with the passed name already exists in the current transaction.
3B502 | A RELEASE or ROLLBACK TO SAVEPOINT was specified, but the savepoint does not exist.

Table 53. Class 40: Transaction Rollback

SQLSTATE | Message Text
40001 | A lock could not be obtained due to a deadlock, cycle of locks and waiters is: <lockCycle>. The selected victim is XID : <transactionID>.
40XC0 | Dead statement. This may be caused by catching a transaction severity error inside this statement.
40XD0 | Container has been closed.
40XD1 | Container was opened in read-only mode.
40XD2 | Container <containerName> cannot be opened; it either has been dropped or does not exist.
40XL1 | A lock could not be obtained within the time requested
40XL2 | A lock could not be obtained within the time requested. The lockTable dump is: <tableDump>
40XT0 | An internal error was identified by RawStore module.
40XT1 | An exception was thrown during transaction commit.
40XT2 | An exception was thrown during rollback of a SAVEPOINT.
40XT4 | An attempt was made to close a transaction that was still active. The transaction has been aborted.
40XT5 | Exception thrown during an internal transaction.
40XT6 | Database is in quiescent state, cannot activate transaction. Please wait for a moment till it exits the quiescent state.
40XT7 | Operation is not supported in an internal transaction.

Table 54. Class 42: Syntax Error or Access Rule Violation

SQLSTATE | Message Text
42000 | Syntax error or access rule violation; see additional errors for details.
42500 | User '<authorizationID>' does not have <permissionType> permission on table '<schemaNamet>'.'<tableName>'.
42501 | User '<authorizationID>' does not have <permissionType> permission on table '<schemaNamet>'.'<tableName>' for grant.
42502 | User '<authorizationID>' does not have <permissionType> permission on column '<columnName>' of table '<schemaName>'.'<tableName>'.
42503 | User '<authorizationID>' does not have <permissionType> permission on column '<columnName>' of table '<schemaName>'.'<tableName>' for grant.
42504 | User '<authorizationID>' does not have execute permission on <objectName> '<schemaName>'.'<tableName>'.
42505 | User '<authorizationID>' does not have execute permission on <objectName> '<schemaName>'.'<tableName>' for grant.
42506 | User '<authorizationID>' is not the owner of <objectName> '<schemaName>'.'<tableName>'.
42507 | User '<authorizationID>' can not perform the operation in schema '<schemaName>'.
42508 | User '<authorizationID>' can not create schema '<schemaName>'. Only database owner could issue this statement.
42509 | Specified grant or revoke operation is not allowed on object '<objectName>'.
4250A | User '<authorizationID>' does not have <permissionName> permission on object '<schemaName>'.'<objectName>'.
4250B | Invalid database authorization property '<value>=<value>'.
4250C | User(s) '<authorizationID>' must not be in both read-only and full-access authorization lists.
4250D | Repeated user(s) '<listName>' in access list '<authorizationID>';
4250E | Internal Error: invalid <authorizationID> id in statement permission list.
42601 | In an ALTER TABLE statement, the column '<columnName>' has been specified as NOT NULL and either the DEFAULT clause was not specified or was specified as DEFAULT NULL.
42601 | ALTER TABLE statement cannot add an IDENTITY column to a table.
42605 | The number of arguments for function '<functionName>' is incorrect.
42606 | An invalid hexadecimal constant starting with '<number>' has been detected.
42610 | All the arguments to the COALESCE/VALUE function cannot be parameters. The function needs at least one argument that is not a parameter.
42611 | The length, precision, or scale attribute for column, or type mapping '<value>' is not valid.
42613 | Multiple or conflicting keywords involving the '<clause>' clause are present.
42621 | A check constraint or generated column that is defined with '<value>' is invalid.
42622 | The name '<name>' is too long. The maximum length is '<number>'.
42734 | Name '<name>' specified in context '<context>' is not unique.
42802 | The number of values assigned is not the same as the number of specified or implied columns.
42803 | An expression containing the column '<columnName>' appears in the SELECT list and is not part of a GROUP BY clause.
42815 | The replacement value for '<value>' is invalid.
42815 | The data type, length or value of arguments '<value>' and '<value>' is incompatible.
42818 | Comparisons between '<type>' and '<type>' are not supported.
42820 | The floating point literal '<string>' contains more than 30 characters.
42821 | Columns of type '<type>' cannot hold values of type '<type>'.
42824 | An operand of LIKE is not a string, or the first operand is not a column.
42831 | '<columnName>' cannot be a column of a primary key or unique key because it can contain null values.
42834 | SET NULL cannot be specified because FOREIGN KEY '<key>' cannot contain null values.
42837 | ALTER TABLE '<tableName>' specified attributes for column '<columnName>' that are not compatible with the existing column.
42846 | Cannot convert types '<type>' to '<type>'.
42877 | A qualified column name '<columnName>' is not allowed in the ORDER BY clause.
42878 | The ORDER BY clause of a SELECT UNION statement only supports unqualified column references and column position numbers. Other expressions are not currently supported.
42884 | No authorized routine named '<routineName>' of type '<type>' having compatible arguments was found.
42886 | '<value>' parameter '<value>' requires a parameter marker '?'.
42894 | DEFAULT value or IDENTITY attribute value is not valid for column '<columnName>'.
428C1 | Only one identity column is allowed in a table.
428EK | The qualifier for a declared global temporary table name must be SESSION.
42903 | Invalid use of an aggregate function.
42908 | The CREATE VIEW statement does not include a column list.
42909 | The CREATE TABLE statement does not include a column list.
42915 | Foreign Key '<key>' is invalid because '<value>'.
42916 | Synonym '<synonym2>' cannot be created for '<synonym1>' as it would result in a circular synonym chain.
42939 | An object cannot be created with the schema name '<schemaNamet>'.
42962 | Long column type column or parameter '<columnName>' not permitted in declared global temporary tables or procedure definitions.
42972 | An ON clause associated with a JOIN operator is not valid.
42995 | The requested function does not apply to global temporary tables.
42X01 | Syntax error: <error>.
42X02 | <value>.
42X03 | Column name '<columnName>' is in more than one table in the FROM list.
42X04 | Column '<columnName>' is either not in any table in the FROM list or appears within a join specification and is outside the scope of the join specification or appears in a HAVING clause and is not in the GROUP BY list. If this is a CREATE or ALTER TABLE statement then '<columnName>' is not a column in the target table.
42X05 | Table/View '<objectName>' does not exist.
42X06 | Too many result columns specified for table '<tableName>'.
42X07 | Null is only allowed in a VALUES clause within an INSERT statement.
42X08 | The constructor for class '<className>' cannot be used as an external virtual table because the class does not implement '<constructorName>'.
42X09 | The table or alias name '<tableName>' is used more than once in the FROM list.
42X10 | '<tableName>' is not an exposed table name in the scope in which it appears.
42X12 | Column name '<columnName>' appears more than once in the CREATE TABLE statement.
42X13 | Column name '<columnName>' appears more than once times in the column list of an INSERT statement.
42X14 | '<columnName>' is not a column in table or VTI '<value>'.
42X15 | Column name '<columnName>' appears in a statement without a FROM list.
42X16 | Column name '<columnName>' appears multiple times in the SET clause of an UPDATE statement.
42X17 | In the Properties list of a FROM clause, the value '<value>' is not valid as a joinOrder specification. Only the values FIXED and UNFIXED are valid.
42X19 | The WHERE or HAVING clause or CHECK CONSTRAINT definition is a '<value>' expression. It must be a BOOLEAN expression.
42X23 | Cursor <cursorName> is not updatable.
42X24 | Column <columnName> is referenced in the HAVING clause but is not in the GROUP BY list.
42X25 | The '<functionName>' function is not allowed on the '<1>' type.
42X26 | The class '<className>' for column '<columnName>' does not exist or is inaccessible. This can happen if the class is not public.
42X28 | Delete table '<tableName>' is not target of cursor '<cursorName>'.
42X29 | Update table '<tableName>' is not the target of cursor '<cursorName>'.
42X30 | Cursor '<cursorName>' not found. Verify that autocommit is OFF.
42X31 | Column '<columnName>' is not in the FOR UPDATE list of cursor '<cursorName>'.
42X32 | The number of columns in the derived column list must match the number of columns in table '<tableName>'.
42X33 | The derived column list contains a duplicate column name '<columnName>'.
42X34 | There is a ? parameter in the select list. This is not allowed.
42X35 | It is not allowed for both operands of '<value>' to be ? parameters.
42X36 | The '<operator>' operator is not allowed to take a ? parameter as an operand.
42X37 | The unary '<operator>' operator is not allowed on the '<type>' type.
42X38 | 'SELECT *' only allowed in EXISTS and NOT EXISTS subqueries.
42X39 | Subquery is only allowed to return a single column.
42X40 | A NOT statement has an operand that is not boolean . The operand of NOT must evaluate to TRUE, FALSE, or UNKNOWN.
42X41 | In the Properties clause of a FROM list, the property '<propertyName>' is not valid (the property was being set to '<value>').
42X42 | Correlation name not allowed for column '<columnName>' because it is part of the FOR UPDATE list.
42X43 | The ResultSetMetaData returned for the class/object '<className>' was null. In order to use this class as an external virtual table, the ResultSetMetaData cannot be null.
42X44 | Invalid length '<number>' in column specification.
42X45 | <type> is an invalid type for argument number <value> of <value>.
42X46 | There are multiple functions named '<functionName>'. Use the full signature or the specific name.
42X47 | There are multiple procedures named '<procedureName>'. Use the full signature or the specific name.
42X48 | Value '<value>' is not a valid precision for <value>.
42X49 | Value '<value>' is not a valid integer literal.
42X50 | No method was found that matched the method call <methodName>.<value>(<value>), tried all combinations of object and primitive types and any possible type conversion for any parameters the method call may have. The method might exist but it is not public and/or static, or the parameter types are not method invocation convertible.
42X51 | The class '<className>' does not exist or is inaccessible. This can happen if the class is not public.
42X52 | Calling method ('<methodName>') using a receiver of the Java primitive type '<type>' is not allowed.
42X53 | The LIKE predicate can only have 'CHAR' or 'VARCHAR' operands. Type '<type>' is not permitted.
42X54 | The Java method '<methodName>' has a ? as a receiver. This is not allowed.
42X55 | Table name '<value>' should be the same as '<tableName>'.
42X56 | The number of columns in the view column list does not match the number of columns in the underlying query expression in the view definition for '<value>'.
42X57 | The getColumnCount() for external virtual table '<tableName>' returned an invalid value '<value>'. Valid values are greater than or equal to 1.
42X58 | The number of columns on the left and right sides of the <tableName> must be the same.
42X59 | The number of columns in each VALUES constructor must be the same.
42X60 | Invalid value '<value>' for insertMode property specified for table '<tableName>'.
42X61 | Types '<type>' and '<type>' are not <value> compatible.
42X62 | '<value>' is not allowed in the '<schemaNamet>' schema.
42X63 | The USING clause did not return any results. No parameters can be set.
42X64 | In the Properties list, the invalid value '<value>' was specified for the useStatistics property. The only valid values are TRUE or FALSE.
42X65 | Index '<index>' does not exist.
42X66 | Column name '<columnName>' appears more than once in the CREATE INDEX statement.
42X68 | No field '<fieldName>' was found belonging to class '<className>'. It may be that the field exists, but it is not public, or that the class does not exist or is not public.
42X69 | It is not allowed to reference a field ('<fieldName>') using a referencing expression of the Java primitive type '<type>'.
42X70 | The number of columns in the table column list does not match the number of columns in the underlying query expression in the table definition for '<value>'.
42X71 | Invalid data type '<datatypeName>' for column '<columnName>'.
42X72 | No static field '<fieldName>' was found belonging to class '<className>'. The field might exist, but it is not public and/or static, or the class does not exist or the class is not public.
42X73 | Method resolution for signature <value>.<value>(<value>) was ambiguous. (No single maximally specific method.)
42X74 | Invalid CALL statement syntax.
42X75 | No constructor was found with the signature <value>(<value>). It may be that the parameter types are not method invocation convertible.
42X76 | At least one column, '<columnName>', in the primary key being added is nullable. All columns in a primary key must be non-nullable.
42X77 | Column position '<columnPosition>' is out of range for the query expression.
42X78 | Column '<columnName>' is not in the result of the query expression.
42X79 | Column name '<columnName>' appears more than once in the result of the query expression.
42X80 | VALUES clause must contain at least one element. Empty elements are not allowed.
42X82 | The USING clause returned more than one row. Only single-row ResultSets are permissible.
42X83 | The constraints on column '<columnName>' require that it be both nullable and not nullable.
42X84 | Index '<index>' was created to enforce constraint '<constraintName>'. It can only be dropped by dropping the constraint.
42X85 | Constraint '<constraintName>'is required to be in the same schema as table '<tableName>'.
42X86 | ALTER TABLE failed. There is no constraint '<constraintName>' on table '<tableName>'.
42X87 | At least one result expression (THEN or ELSE) of the '<expression>' expression must not be a '?'.
42X88 | A conditional has a non-Boolean operand. The operand of a conditional must evaluate to TRUE, FALSE, or UNKNOWN.
42X89 | Types '<type>' and '<type>' are not type compatible. Neither type is assignable to the other type.
42X90 | More than one primary key constraint specified for table '<tableName>'.
42X91 | Constraint name '<constraintName>' appears more than once in the CREATE TABLE statement.
42X92 | Column name '<columnName>' appears more than once in a constraint's column list.
42X93 | Table '<tableName>' contains a constraint definition with column '<columnName>' which is not in the table.
42X94 | <value> '<value>' does not exist.
42X96 | The database class path contains an unknown jar file '<fileName>'.
42X98 | Parameters are not allowed in a VIEW definition.
42X99 | Parameters are not allowed in a TABLE definition.
42Y00 | Class '<className>' does not implement org.apache.derby.iapi.db.AggregateDefinition and thus cannot be used as an aggregate expression.
42Y01 | Constraint '<constraintName>' is invalid.
42Y03 | '<statement>' is not recognized as a function or procedure.
42Y04 | Cannot create a procedure or function with EXTERNAL NAME '<name>' because it is not a list separated by periods. The expected format is <full java path>.<method name>.
42Y05 | There is no Foreign Key named '<key>'.
42Y07 | Schema '<schemaNamet>' does not exist
42Y08 | Foreign key constraints are not allowed on system tables.
42Y09 | Void methods are only allowed within a CALL statement.
42Y10 | A table constructor that is not in an INSERT statement has all ? parameters in one of its columns. For each column, at least one of the rows must have a non-parameter.
42Y11 | A join specification is required with the '<clauseName>' clause.
42Y12 | The ON clause of a JOIN is a '<expressionType>' expression. It must be a BOOLEAN expression.
42Y13 | Column name '<columnName>' appears more than once in the CREATE VIEW statement.
42Y16 | No public static method '<methodName>' was found in class '<className>'. The method might exist, but it is not public, or it is not static.
42Y22 | Aggregate <aggregateType> cannot operate on type <type>.
42Y23 | Incorrect JDBC type info returned for column <colunmName>.
42Y24 | View '<viewName>' is not updatable. (Views are currently not updatable.)
42Y25 | '<tableName>' is a system table. Users are not allowed to modify the contents of this table.
42Y26 | Aggregates are not allowed in the GROUP BY list.
42Y27 | Parameters are not allowed in the trigger action.
42Y29 | The SELECT list of a non-grouped query contains at least one invalid expression. When the SELECT list contains at least one aggregate then all entries must be valid aggregate expressions.
42Y30 | The SELECT list of a grouped query contains at least one invalid expression. If a SELECT list has a GROUP BY, the list may only contain valid grouping expressions and valid aggregate expressions.
42Y32 | Aggregator class '<className>' for aggregate '<aggregateName>' on type <type> does not implement com.ibm.db2j.aggregates.Aggregator.
42Y33 | Aggregate <aggregateName> contains one or more aggregates.
42Y34 | Column name '<columnName>' matches more than one result column in table '<tableName>'.
42Y35 | Column reference '<reference>' is invalid. When the SELECT list contains at least one aggregate then all entries must be valid aggregate expressions.
42Y36 | Column reference '<reference>' is invalid. For a SELECT list with a GROUP BY, the list may only contain valid grouping expressions and valid aggregate expressions.
42Y37 | '<value>' is a Java primitive and cannot be used with this operator.
42Y38 | insertMode = replace is not permitted on an insert where the target table, '<tableName>', is referenced in the SELECT.
42Y39 | '<value>' may not appear in a CHECK CONSTRAINT definition because it may return non-deterministic results.
42Y40 | '<value>' appears multiple times in the UPDATE OF column list for trigger '<triggerName>'.
42Y41 | '<value>' cannot be directly invoked via EXECUTE STATEMENT because it is part of a trigger.
42Y42 | Scale '<value>' is not a valid scale for a <scaleValue>.
42Y43 | Scale '<scaleValue>' is not a valid scale with precision of '<precision>'.
42Y44 | Invalid key '<key>' specified in the Properties list of a FROM list. The case-sensitive keys that are currently supported are '<key>'.
42Y45 | VTI '<value>' cannot be bound because it is a special trigger VTI and this statement is not part of a trigger action or WHEN clause.
42Y46 | Invalid Properties list in FROM list. There is no index '<index>' on table '<tableName>'.
42Y48 | Invalid Properties list in FROM list. Either there is no named constraint '<constraintName>' on table '<tableName>' or the constraint does not have a backing index.
42Y49 | Multiple values specified for property key '<key>'.
42Y50 | Properties list for table '<tableName>' may contain values for index or for constraint but not both.
42Y55 | '<value>' cannot be performed on '<value>' because it does not exist.
42Y56 | Invalid join strategy '<strategyValue>' specified in Properties list on table '<tableName>'. The currently supported values for a join strategy are: 'hash' and 'nestedloop'.
42Y58 | NumberFormatException occurred when converting value '<value>' for optimizer override '<value>'.
42Y59 | Invalid value, '<value>', specified for hashInitialCapacity override. Value must be greater than 0.
42Y60 | Invalid value, '<value>', specified for hashLoadFactor override. Value must be greater than 0.0 and less than or equal to 1.0.
42Y61 | Invalid value, '<value>', specified for hashMaxCapacity override. Value must be greater than 0.
42Y62 | '<statement>' is not allowed on '<viewName>' because it is a view.
42Y63 | Hash join requires an optimizable equijoin predicate on a column in the selected index or heap. An optimizable equijoin predicate does not exist on any column in table or index '<index>'. Use the 'index' optimizer override to specify such an index or the heap on table '<tableName>'.
42Y64 | bulkFetch value of '<value>' is invalid. The minimum value for bulkFetch is 1.
42Y65 | bulkFetch is not permitted on '<joinType>' joins.
42Y66 | bulkFetch is not permitted on updatable cursors.
42Y67 | Schema '<schemaNamet>' cannot be dropped.
42Y69 | No valid execution plan was found for this statement. This may have one of two causes: either you specified a hash join strategy when hash join is not allowed (no optimizable equijoin) or you are attempting to join two external virtual tables, each of which references the other, and so the statement cannot be evaluated.
42Y70 | The user specified an illegal join order. This could be caused by a join column from an inner table being passed as a parameter to an external virtual table.
42Y71 | System function or procedure '<procedureName>' cannot be dropped.
42Y82 | System generated stored prepared statement '<statement>' that cannot be dropped using DROP STATEMENT. It is part of a trigger.
42Y83 | An untyped null is not permitted as an argument to aggregate <aggregateName>. Please cast the null to a suitable type.
42Y84 | '<value>' may not appear in a DEFAULT definition.
42Y85 | The DEFAULT keyword is only allowed in a VALUES clause when the VALUES clause appears within an INSERT statement.
42Y90 | FOR UPDATE is not permitted in this type of statement.
42Y91 | The USING clause is not permitted in an EXECUTE STATEMENT for a trigger action.
42Y92 | <triggerName> triggers may only reference <value> transition variables/tables.
42Y93 | Illegal REFERENCING clause: only one name is permitted for each type of transition variable/table.
42Y94 | An AND or OR has a non-boolean operand. The operands of AND and OR must evaluate to TRUE, FALSE, or UNKNOWN.
42Y95 | The '<operatorName>' operator with a left operand type of '<operandType>' and a right operand type of '<operandType>' is not supported.
42Y97 | Invalid escape character at line '<lineNumber>', column '<columnName>'.
42Z02 | Multiple DISTINCT aggregates are not supported at this time.
42Z07 | Aggregates are not permitted in the ON clause.
42Z08 | Bulk insert replace is not permitted on '<value>' because it has an enabled trigger (<value>).
42Z15 | Invalid type specified for column '<columnName>'. The type of a column may not be changed.
42Z16 | Only columns of type VARCHAR may have their length altered.
42Z17 | Invalid length specified for column '<columnName>'. Length must be greater than the current column length.
42Z18 | Column '<columnName>' is part of a foreign key constraint '<constraintName>'. To alter the length of this column, you should drop the constraint first, perform the ALTER TABLE, and then recreate the constraint.
42Z19 | Column '<columnName>' is being referenced by at least one foreign key constraint '<constraintName>'. To alter the length of this column, you should drop referencing constraints, perform the ALTER TABLE and then recreate the constraints.
42Z20 | Column '<columnName>' cannot be made nullable. It is part of a primary key or unique constraint, which cannot have any nullable columns.
42Z21 | Invalid increment specified for identity for column '<columnName>'. Increment cannot be zero.
42Z22 | Invalid type specified for identity column '<columnName>'. The only valid types for identity columns are BIGINT, INT and SMALLINT.
42Z23 | Attempt to modify an identity column '<columnName>'.
42Z24 | Overflow occurred in identity value for column '<tableName>' in table '<columnName>'.
42Z25 | INTERNAL ERROR identity counter. Update was called without arguments with current value \= NULL.
42Z26 | A column, '<columnName>', with an identity default cannot be made nullable.
42Z27 | A nullable column, '<columnName>', cannot be modified to have identity default.
42Z50 | INTERNAL ERROR: Unable to generate code for <value>.
42Z53 | INTERNAL ERROR: Type of activation to generate for node choice <value> is unknown.
42Z60 | <value> not allowed unless database property <propertyName> has value '<value>'.
42Z70 | Binding directly to an XML value is not allowed; try using XMLPARSE.
42Z71 | XML values are not allowed in top-level result sets; try using XMLSERIALIZE.
42Z72 | Missing SQL/XML keyword(s) '<keywords>' at line <lineNumber>, column <columnNumber>.
42Z73 | Invalid target type for XMLSERIALIZE: '<typeName>'.
42Z74 | XML feature not supported: '<featureName>'.
42Z75 | XML query expression must be a string literal.
42Z76 | Multiple XML context items are not allowed.
42Z77 | Context item must have type 'XML'; '<value>' is not allowed.
42Z79 | Unable to determine the parameter type for XMLPARSE; try using a CAST.
42Z90 | Class '<className>' does not return an updatable ResultSet.
42Z91 | subquery
42Z92 | repeatable read
42Z93 | Constraints '<constraintName>' and '<constraintName>' have the same set of columns, which is not allowed.
42Z97 | Renaming column '<columnName>' will cause check constraint '<constraintName>' to break.
42Z99 | String or Hex literal cannot exceed 64K.
42Z9A | read uncommitted
42Z9B | The external virtual table interface does not support BLOB or CLOB columns. '<value>' column '<value>'.
42Z9D | Procedures that modify SQL data are not allowed in BEFORE triggers.
42Z9D | '<statement>' statements are not allowed in '<triggerName>' triggers.
42Z9E | Constraint '<constraintName>' is not a <value> constraint.
42Z9F | Too many indexes (<index>) on the table <tableName>. The limit is <number>.
42ZA0 | Statement too complex. Try rewriting the query to remove complexity. Eliminating many duplicate expressions or breaking up the query and storing interim results in a temporary table can often help resolve this error.
42ZA1 | Invalid SQL in Batch: '<batch>'.
42ZA2 | Operand of LIKE predicate with type <type> and collation <value> is not compatable with LIKE pattern operand with type <type> and collation <value>.
42ZA3 | The table will have collation type <type> which is different than the collation of the schema <type> hence this operation is not supported .

Table 55. Class 57: DRDA Network Protocol: Execution Failure

SQLSTATE | Message Text
57017 | There is no available conversion for the source code page, <codePage>, to the target code page, <codePage>. The connection has been terminated.

Table 56. Class 58: DRDA Network Protocol: Protocol Error

SQLSTATE | Message Text
58009 | Network protocol exception: only one of the VCM, VCS length can be greater than 0. The connection has been terminated.
58009 | The connection was terminated because the encoding is not supported.
58009 | Network protocol exception: actual code point, <value>, does not match expected code point, <value>. The connection has been terminated.
58009 | Network protocol exception: DDM collection contains less than 4 bytes of data. The connection has been terminated.
58009 | Network protocol exception: collection stack not empty at end of same id chain parse. The connection has been terminated.
58009 | Network protocol exception: DSS length not 0 at end of same id chain parse. The connection has been terminated.
58009 | Network protocol exception: DSS chained with same id at end of same id chain parse. The connection has been terminated.
58009 | Network protocol exception: end of stream prematurely reached while reading InputStream, parameter #<value>. The connection has been terminated.
58009 | Network protocol exception: invalid FDOCA LID. The connection has been terminated.
58009 | Network protocol exception: SECTKN was not returned. The connection has been terminated.
58009 | Network protocol exception: only one of NVCM, NVCS can be non-null. The connection has been terminated.
58009 | Network protocol exception: SCLDTA length, <length>, is invalid for RDBNAM. The connection has been terminated.
58009 | SocketException: '<error>'
58009 | A communications error has been detected: <error>.
58009 | An error occurred during a deferred connect reset and the connection has been terminated. See chained exceptions for details.
58009 | Insufficient data while reading from the network - expected a minimum of <number> bytes and received only <number> bytes. The connection has been terminated.
58009 | Attempt to fully materialize lob data that is too large for the JVM. The connection has been terminated.
58009 | Network protocol exception: SCLDTA length, <length>, is invalid for RDBCOLID. The connection has been terminated.
58009 | Network protocol exception: SCLDTA length, <length>, is invalid for PKGID. The connection has been terminated.
58009 | Network protocol exception: PKGNAMCSN length, <length>, is invalid at SQLAM <value>. The connection has been terminated.
58009 | A network protocol error was encountered and the connection has been terminated: <error>
58010 | A network protocol error was encountered. A connection could not be established because the manager <value> at level <value> is not supported by the server.
58014 | The DDM command 0x<value> is not supported. The connection has been terminated.
58015 | The DDM object 0x<value> is not supported. The connection has been terminated.
58016 | The DDM parameter 0x<value> is not supported. The connection has been terminated.
58017 | The DDM parameter value 0x<value> is not supported. An input host variable may not be within the range the server supports. The connection has been terminated.

Table 57. Class X0: Execution exceptions

SQLSTATE | Message Text
X0A00 | The select list mentions column '<columnName>' twice. This is not allowed in queries with GROUP BY or HAVING clauses. Try aliasing one of the conflicting columns to a unique name.
X0X02 | Table '<tableName>' cannot be locked in '<mode>' mode.
X0X03 | Invalid transaction state - held cursor requires same isolation level
X0X05 | Table/View '<tableName>' does not exist.
X0X07 | Cannot remove jar file '<fileName>' because it is on your derby.database.classpath '<fileName>'.
X0X0E | Table '<tableName>' does not have an auto-generated column at column position '<columnPosition>'.
X0X0F | Table '<tableName>' does not have an auto-generated column named '<columnName>'.
X0X10 | The USING clause returned more than one row; only single-row ResultSets are permissible.
X0X11 | The USING clause did not return any results so no parameters can be set.
X0X13 | Jar file '<fileName>' does not exist in schema '<schemaNamet>'.
X0X57 | An attempt was made to put a Java value of type '<type>' into a SQL value, but there is no corresponding SQL type. The Java value is probably the result of a method call or field access.
X0X60 | A cursor with name '<cursorName>' already exists.
X0X61 | The values for column '<location>' in index '<columnName>' and table '<indexName>.<schemaNamet>' do not match for row location <tableName>. The value in the index is '<value>', while the value in the base table is '<value>'. The full index key, including the row location, is '<indexKey>'. The suggested corrective action is to recreate the index.
X0X62 | Inconsistency found between table '<tableName>' and index '<indexName>'. Error when trying to retrieve row location '<rowLocation>' from the table. The full index key, including the row location, is '<indexKey>'. The suggested corrective action is to recreate the index.
X0X63 | Got IOException '<value>'.
X0X67 | Columns of type '<type>' may not be used in CREATE INDEX, ORDER BY, GROUP BY, UNION, INTERSECT, EXCEPT or DISTINCT statements because comparisons are not supported for that type.
X0X81 | <value> '<value>' does not exist.
X0X85 | Index '<indexName>' was not created because '<indexType>' is not a valid index type.
X0X86 | 0 is an invalid parameter value for ResultSet.absolute(int row).
X0X87 | ResultSet.relative(int row) cannot be called when the cursor is not positioned on a row.
X0X95 | Operation '<operationName>' cannot be performed on object '<objectName>' because there is an open ResultSet dependent on that object.
X0X99 | Index '<indexName>' does not exist.
X0Y16 | '<value>' is not a view. If it is a table, then use DROP TABLE instead.
X0Y23 | Operation '<operationName>' cannot be performed on object '<objectName>' because VIEW '<viewName>' is dependent on that object.
X0Y24 | Operation '<operationName>' cannot be performed on object '<objectName>' because STATEMENT '<statement>' is dependent on that object.
X0Y25 | Operation '<operationName>' cannot be performed on object '<objectName>' because <value> '<value>' is dependent on that object.
X0Y26 | Index '<indexName>' is required to be in the same schema as table '<tableName>'.
X0Y28 | Index '<indexName>' cannot be created on system table '<tableName>'. Users cannot create indexes on system tables.
X0Y32 | <value> '<value>' already exists in <value> '<value>'.
X0Y38 | Cannot create index '<indexName>' because table '<tableName>' does not exist.
X0Y41 | Constraint '<constraintName>' is invalid because the referenced table <tableName> has no primary key. Either add a primary key to <tableName> or explicitly specify the columns of a unique constraint that this foreign key references.
X0Y42 | Constraint '<constraintName>' is invalid: the types of the foreign key columns do not match the types of the referenced columns.
X0Y43 | Constraint '<constraintName>' is invalid: the number of columns in <constraintName> (<value>) does not match the number of columns in the referenced key (<value>).
X0Y44 | Constraint '<constraintName>' is invalid: there is no unique or primary key constraint on table '<tableName>' that matches the number and types of the columns in the foreign key.
X0Y45 | Foreign key constraint '<constraintName>' cannot be added to or enabled on table <tableName> because one or more foreign keys do not have matching referenced keys.
X0Y46 | Constraint '<constraintName>' is invalid: referenced table <tableName> does not exist.
X0Y54 | Schema '<schemaNamet>' cannot be dropped because it is not empty.
X0Y55 | The number of rows in the base table does not match the number of rows in at least 1 of the indexes on the table. Index '<indexName>' on table '<schemaNamet>.<tableName>' has <number> rows, but the base table has <number> rows. The suggested corrective action is to recreate the index.
X0Y56 | '<value>' is not allowed on the System table '<tableName>'.
X0Y57 | A non-nullable column cannot be added to table '<tableName>' because the table contains at least one row. Non-nullable columns can only be added to empty tables.
X0Y58 | Attempt to add a primary key constraint to table '<tableName>' failed because the table already has a constraint of that type. A table can only have a single primary key constraint.
X0Y59 | Attempt to add or enable constraint(s) on table '<rowName>' failed because the table contains <constraintName> row(s) that violate the following check constraint(s): <tableName>.
X0Y63 | The command on table '<tableName>' failed because null data was found in the primary key or unique constraint/index column(s). All columns in a primary or unique index key must not be null.
X0Y66 | Cannot issue commit in a nested connection when there is a pending operation in the parent connection.
X0Y67 | Cannot issue rollback in a nested connection when there is a pending operation in the parent connection.
X0Y68 | <value> '<value>' already exists.
X0Y69 | <triggerName> is not supported in trigger <value>.
X0Y70 | INSERT, UPDATE and DELETE are not permitted on table <triggerName> because trigger <tableName> is active.
X0Y71 | Transaction manipulation such as SET ISOLATION is not permitted because trigger <triggerName> is active.
X0Y72 | Bulk insert replace is not permitted on '<value>' because it has an enabled trigger (<value>).
X0Y77 | Cannot issue set transaction isolation statement on a global transaction that is in progress because it would have implicitly committed the global transaction.
X0Y78 | Statement.executeQuery() cannot be called with a statement that returns a row count.
X0Y78 | <value>.executeQuery() cannot be called because multiple result sets were returned. Use <value>.execute() to obtain multiple results.
X0Y78 | <value>.executeQuery() was called but no result set was returned. Use <value>.executeUpdate() for non-queries.
X0Y79 | Statement.executeUpdate() cannot be called with a statement that returns a ResultSet.
X0Y80 | ALTER table '<tableName>' failed. Null data found in column '<columnName>'.
X0Y83 | WARNING: While deleting a row from a table the index row for base table row <rowName> was not found in index with conglomerate id <id>. This problem has automatically been corrected as part of the delete operation.

Table 58. Class XBCA: CacheService

SQLSTATE | Message Text
XBCA0 | Cannot create new object with key <cache> in <key> cache. The object already exists in the cache.

Table 59. Class XBCM: ClassManager

SQLSTATE | Message Text
XBCM1 | Java linkage error thrown during load of generated class <className>.
XBCM2 | Cannot create an instance of generated class <className>.
XBCM3 | Method <className>() does not exist in generated class <methodName>.
XBCM4 | Java class file format limit(s) exceeded: <className> in generated class <value>.

Table 60. Class XBCX: Cryptography

SQLSTATE | Message Text
XBCX0 | Exception from Cryptography provider. See next exception for details.
XBCX1 | Initializing cipher with illegal mode, must be either ENCRYPT or DECRYPT.
XBCX2 | Initializing cipher with a boot password that is too short. The password must be at least <number> characters long.
XBCX5 | Cannot change boot password to null.
XBCX6 | Cannot change boot password to a non-string serializable type.
XBCX7 | Wrong format for changing boot password. Format must be : old_boot_password, new_boot_password.
XBCX8 | Cannot change boot password for a non-encrypted database.
XBCX9 | Cannot change boot password for a read-only database.
XBCXA | Wrong boot password.
XBCXB | Bad encryption padding '<value>' or padding not specified. 'NoPadding' must be used.
XBCXC | Encryption algorithm '<algorithmName>' does not exist. Please check that the chosen provider '<providerName>' supports this algorithm.
XBCXD | The encryption algorithm cannot be changed after the database is created.
XBCXE | The encryption provider cannot be changed after the database is created.
XBCXF | The class '<className>' representing the encryption provider cannot be found.
XBCXG | The encryption provider '<providerName>' does not exist.
XBCXH | The encryptionAlgorithm '<algorithmName>' is not in the correct format. The correct format is algorithm/feedbackMode/NoPadding.
XBCXI | The feedback mode '<mode>' is not supported. Supported feedback modes are CBC, CFB, OFB and ECB.
XBCXJ | The application is using a version of the Java Cryptography Extension (JCE) earlier than 1.2.1. Please upgrade to JCE 1.2.1 and try the operation again.
XBCXK | The given encryption key does not match the encryption key used when creating the database. Please ensure that you are using the correct encryption key and try again.
XBCXL | The verification process for the encryption key was not successful. This could have been caused by an error when accessing the appropriate file to do the verification process. See next exception for details.
XBCXM | The length of the external encryption key must be an even number.
XBCXN | The external encryption key contains one or more illegal characters. Allowed characters for a hexadecimal number are 0-9, a-f and A-F.
XBCXO | Cannot encrypt the database when there is a global transaction in the prepared state.
XBCXP | Cannot re-encrypt the database with a new boot password or an external encryption key when there is a global transaction in the prepared state.
XBCXQ | Cannot configure a read-only database for encryption.
XBCXR | Cannot re-encrypt a read-only database with a new boot password or an external encryption key .
XBCXS | Cannot configure a database for encryption, when database is in the log archive mode.
XBCXT | Cannot re-encrypt a database with a new boot password or an external encryption key, when database is in the log archive mode.
XBCXU | Encryption of an un-encrypted database failed: <failureMessage>
XBCXV | Encryption of an encrypted database with a new key or a new password failed: <failureMessage>

Table 61. Class XBM: Monitor

SQLSTATE | Message Text
XBM01 | Startup failed due to an exception. See next exception for details.
XBM02 | Startup failed due to missing functionality for <value>. Please ensure your classpath includes the correct Derby software.
XBM05 | Startup failed due to missing product version information for <value>.
XBM06 | Startup failed. An encrypted database cannot be accessed without the correct boot password.
XBM07 | Startup failed. Boot password must be at least 8 bytes long.
XBM08 | Could not instantiate <value> StorageFactory class <value>.
XBM0G | Failed to start encryption engine. Please make sure you are running Java 2 and have downloaded an encryption provider such as jce and put it in your class path.
XBM0H | Directory <directoryName> cannot be created.
XBM0I | Directory <directoryName> cannot be removed.
XBM0J | Directory <directoryName> already exists.
XBM0K | Unknown sub-protocol for database name <databaseName>.
XBM0L | Specified authentication scheme class <className> does implement the authentication interface <interfaceName>.
XBM0M | Error creating instance of authentication scheme class <className>.
XBM0N | JDBC Driver registration with java.sql.DriverManager failed. See next exception for details.
XBM0P | Service provider is read-only. Operation not permitted.
XBM0Q | File <fileName> not found. Please make sure that backup copy is the correct one and it is not corrupted.
XBM0R | Unable to remove File <fileName>.
XBM0S | Unable to rename file '<fileName>' to '<fileName>'
XBM0T | Ambiguous sub-protocol for database name <databaseName>.
XBM0U | No class was registered for identifier <identifierName>.
XBM0V | An exception was thrown while loading class <identifierName> registered for identifier <className>.
XBM0W | An exception was thrown while creating an instance of class <identifierName> registered for identifier <className>.
XBM0X | Supplied territory description '<value>' is invalid, expecting ln[_CO[_variant]] ln=lower-case two-letter ISO-639 language code, CO=upper-case two-letter ISO-3166 country codes, see java.util.Locale.
XBM03 | Supplied value '<value>' for collation attribute is invalid, expecting UCS_BASIC or TERRITORY_BASED.
XBM0Y | Backup database directory <directoryName> not found. Please make sure that the specified backup path is right.
XBM0Z | Unable to copy file '<fileName>' to '<fileName>'. Please make sure that there is enough space and permissions are correct.

Table 62. Class XCL: Execution exceptions

SQLSTATE | Message Text
XCL01 | Result set does not return rows. Operation <operationName> not permitted.
XCL05 | Activation closed, operation <operationName> not permitted.
XCL07 | Cursor '<cursorName>' is closed. Verify that autocommit is OFF.
XCL08 | Cursor '<cursorName>' is not on a row.
XCL09 | An Activation was passed to the '<methodName>' method that does not match the PreparedStatement.
XCL10 | A PreparedStatement has been recompiled and the parameters have changed. If you are using JDBC you must prepare the statement again.
XCL12 | An attempt was made to put a data value of type '<datatypeName>' into a data value of type '<datatypeName>'.
XCL13 | The parameter position '<parameterPosition>' is out of range. The number of parameters for this prepared statement is '<number>'.
XCL14 | The column position '<columnPosition>' is out of range. The number of columns for this ResultSet is '<number>'.
XCL15 | A ClassCastException occurred when calling the compareTo() method on an object '<object>'. The parameter to compareTo() is of class '<className>'.
XCL16 | ResultSet not open. Operation '<operation>' not permitted. Verify that autocommit is OFF.
XCL16 | ResultSet not open. Verify that autocommit is OFF.
XCL17 | Statement not allowed in this database.
XCL18 | Stream of column value in result cannot be retrieved twice
XCL19 | Missing row in table '<tableName>' for key '<key>'.
XCL20 | Catalogs at version level '<versionNumber>' cannot be upgraded to version level '<versionNumber>'.
XCL21 | You are trying to execute a Data Definition statement (CREATE, DROP, or ALTER) while preparing a different statement. This is not allowed. It can happen if you execute a Data Definition statement from within a static initializer of a Java class that is being used from within a SQL statement.
XCL22 | Parameter <parameterName> cannot be registered as an OUT parameter because it is an IN parameter.
XCL23 | SQL type number '<type>' is not a supported type by registerOutParameter().
XCL24 | Parameter <parameterName> appears to be an output parameter, but it has not been so designated by registerOutParameter(). If it is not an output parameter, then it has to be set to type <type>.
XCL25 | Parameter <parameterName> cannot be registered to be of type <type> because it maps to type <type> and they are incompatible.
XCL26 | Parameter <parameterName> is not an output parameter.
XCL27 | Return output parameters cannot be set.
XCL30 | An IOException was thrown when reading a '<value>' from an InputStream.
XCL31 | Statement closed.
XCL33 | The table cannot be defined as a dependent of table <tableName> because of delete rule restrictions. (The relationship is self-referencing and a self-referencing relationship already exists with the SET NULL delete rule.)
XCL34 | The table cannot be defined as a dependent of table <tableName> because of delete rule restrictions. (The relationship forms a cycle of two or more tables that cause the table to be delete-connected to itself (all other delete rules in the cycle would be CASCADE)).
XCL35 | The table cannot be defined as a dependent of table <tableName> because of delete rule restrictions. (The relationship causes the table to be delete-connected to the indicated table through multiple relationships and the delete rule of the existing relationship is SET NULL.).
XCL36 | The delete rule of foreign key must be <value>. (The referential constraint is self-referencing and an existing self-referencing constraint has the indicated delete rule (NO ACTION, RESTRICT or CASCADE).)
XCL37 | The delete rule of foreign key must be <value>. (The referential constraint is self-referencing and the table is dependent in a relationship with a delete rule of CASCADE.)
XCL38 | the delete rule of foreign key must be <ruleName>. (The relationship would cause the table to be delete-connected to the same table through multiple relationships and such relationships must have the same delete rule (NO ACTION, RESTRICT or CASCADE).)
XCL39 | The delete rule of foreign key cannot be CASCADE. (A self-referencing constraint exists with a delete rule of SET NULL, NO ACTION or RESTRICT.)
XCL40 | The delete rule of foreign key cannot be CASCADE. (The relationship would form a cycle that would cause a table to be delete-connected to itself. One of the existing delete rules in the cycle is not CASCADE, so this relationship may be definable if the delete rule is not CASCADE.)
XCL41 | the delete rule of foreign key can not be CASCADE. (The relationship would cause another table to be delete-connected to the same table through multiple paths with different delete rules or with delete rule equal to SET NULL.)
XCL42 | CASCADE
XCL43 | SET NULL
XCL44 | RESTRICT
XCL45 | NO ACTION
XCL46 | SET DEFAULT
XCL47 | Use of '<value>' requires database to be upgraded from version <versionNumber> to version <versionNumber> or later.
XCL48 | TRUNCATE TABLE is not permitted on '<value>' because unique/primary key constraints on this table are referenced by enabled foreign key constraints from other tables.
XCL49 | TRUNCATE TABLE is not permitted on '<value>' because it has an enabled DELETE trigger (<value>).
XCL50 | Upgrading the database from a previous version is not supported. The database being accessed is at version level '<versionNumber>', this software is at version level '<versionNumber>'.
XCL51 | The requested function can not reference tables in SESSION schema.
XCL52 | The statement has been cancelled or timed out.
XCL53 | Stream is closed

Table 63. Class XCW: Upgrade unsupported

SQLSTATE | Message Text
XCW00 | Unsupported upgrade from '<value>' to '<value>'.

Table 64. Class XCX: Internal Utility Errors

SQLSTATE | Message Text
XCXA0 | Invalid identifier.
XCXB0 | Invalid database classpath: '<classpath>'.
XCXC0 | Invalid id list.
XCXE0 | You are trying to do an operation that uses the territory of the database, but the database does not have a territory.

Table 65. Class XCY: Derby Property Exceptions

SQLSTATE | Message Text
XCY00 | Invalid value for property '<value>'='<value>'.
XCY02 | The requested property change is not supported '<value>'='<value>'.
XCY03 | Required property '<propertyName>' has not been set.
XCY04 | Invalid syntax for optimizer overrides. The syntax should be -- DERBY-PROPERTIES propertyName = value [, propertyName = value]*

Table 66. Class XCZ: org.apache.derby.database.UserUtility

SQLSTATE | Message Text
XCZ00 | Unknown permission '<permissionName>'.
XCZ01 | Unknown user '<authorizationID>'.
XCZ02 | Invalid parameter '<value>'='<value>'.

Table 67. Class XD00: Dependency Manager

SQLSTATE | Message Text
XD003 | Unable to restore dependency from disk. DependableFinder = '<value>'. Further information: '<value>'.
XD004 | Unable to store dependencies.

Table 68. Class XIE: Import/Export Exceptions

SQLSTATE | Message Text
XIE01 | Connection was null.
XIE03 | Data found on line <lineNumber> for column <columnName> after the stop delimiter.
XIE04 | Data file not found: <fileName>
XIE05 | Data file cannot be null.
XIE06 | Entity name was null.
XIE07 | Field and record separators cannot be substrings of each other.
XIE08 | There is no column named: <columnName>.
XIE09 | The total number of columns in the row is: <number>.
XIE0B | Column '<columnName>' in the table is of type <type>, it is not supported by the import/export feature.
XIE0D | Cannot find the record separator on line <lineNumber>.
XIE0E | Read endOfFile at unexpected place on line <lineNumber>.
XIE0I | An IOException occurred while writing data to the file.
XIE0J | A delimiter is not valid or is used more than once.
XIE0K | The period was specified as a character string delimiter.
XIE0M | Table '<tableName>' does not exist.
XIE0N | An invalid hexadecimal string '<hexString>' detected in the import file.
XIE0P | Lob data file <fileName> referenced in the import file not found.
XIE0Q | Lob data file name cannot be null.
XIE0R | Import error on line <lineNumber> of file <fileName>: <details>

Table 69. Class XJ: Connectivity Errors

SQLSTATE | Message Text
XJ004 | Database '<databaseName>' not found.
XJ008 | Cannot rollback or release a savepoint when in auto-commit mode.
XJ009 | Use of CallableStatement required for stored procedure call or use of output parameters: <value>
XJ010 | Cannot issue savepoint when autoCommit is on.
XJ011 | Cannot pass null for savepoint name.
XJ012 | '<value>' already closed.
XJ013 | No ID for named savepoints.
XJ014 | No name for un-named savepoints.
XJ015 | Derby system shutdown.
XJ016 | Method '<methodName>' not allowed on prepared statement.
XJ017 | No savepoint command allowed inside the trigger code.
XJ018 | Column name cannot be null.
XJ020 | Object type not convertible to TYPE '<typeName>', invalid java.sql.Types value, or object was null.
XJ021 | Type is not supported.
XJ022 | Unable to set stream: '<name>'.
XJ023 | Input stream did not have exact amount of data as the requested length.
XJ025 | Input stream cannot have negative length.
XJ028 | The URL '<urlValue>' is not properly formed.
XJ030 | Cannot set AUTOCOMMIT ON when in a nested connection.
XJ040 | Failed to start database '<databaseName>', see the next exception for details.
XJ041 | Failed to create database '<databaseName>', see the next exception for details.
XJ042 | '<value>' is not a valid value for property '<propertyName>'.
XJ044 | '<value>' is an invalid scale.
XJ045 | Invalid or (currently) unsupported isolation level, '<levelName>', passed to Connection.setTransactionIsolation(). The currently supported values are java.sql.Connection.TRANSACTION_SERIALIZABLE, java.sql.Connection.TRANSACTION_REPEATABLE_READ, java.sql.Connection.TRANSACTION_READ_COMMITTED, and java.sql.Connection.TRANSACTION_READ_UNCOMMITTED.
XJ049 | Conflicting create attributes specified.
XJ04B | Batch cannot contain a command that attempts to return a result set.
XJ04C | CallableStatement batch cannot contain output parameters.
XJ056 | Cannot set AUTOCOMMIT ON when in an XA connection.
XJ057 | Cannot commit a global transaction using the Connection, commit processing must go thru XAResource interface.
XJ058 | Cannot rollback a global transaction using the Connection, commit processing must go thru XAResource interface.
XJ059 | Cannot close a connection while a global transaction is still active.
XJ05B | JDBC attribute '<attributeName>' has an invalid value '<value>', valid values are '<value>'.
XJ05C | Cannot set holdability ResultSet.HOLD_CURSORS_OVER_COMMIT for a global transaction.
XJ061 | The '<methodName>' method is only allowed on scroll cursors.
XJ062 | Invalid parameter value '<value>' for ResultSet.setFetchSize(int rows).
XJ063 | Invalid parameter value '<value>' for Statement.setMaxRows(int maxRows). Parameter value must be >= 0.
XJ064 | Invalid parameter value '<value>' for setFetchDirection(int direction).
XJ065 | Invalid parameter value '<value>' for Statement.setFetchSize(int rows).
XJ066 | Invalid parameter value '<value>' for Statement.setMaxFieldSize(int max).
XJ067 | SQL text pointer is null.
XJ068 | Only executeBatch and clearBatch allowed in the middle of a batch.
XJ069 | No SetXXX methods allowed in case of USING execute statement.
XJ070 | Negative or zero position argument '<argument>' passed in a Blob or Clob method.
XJ071 | Negative length argument '<argument>' passed in a BLOB or CLOB method.
XJ072 | Null pattern or searchStr passed in to a BLOB or CLOB position method.
XJ073 | The data in this BLOB or CLOB is no longer available. The BLOB/CLOB's transaction may be committed, or its connection is closed.
XJ074 | Invalid parameter value '<value>' for Statement.setQueryTimeout(int seconds).
XJ076 | The position argument '<positionArgument>' exceeds the size of the BLOB/CLOB.
XJ077 | Got an exception when trying to read the first byte/character of the BLOB/CLOB pattern using getBytes/getSubString.
XJ078 | Offset '<value>' is either less than zero or is too large for the current BLOB/CLOB.
XJ079 | The length specified '<number>' exceeds the size of the BLOB/BLOB.
XJ080 | USING execute statement passed <number> parameters rather than <number>.
XJ081 | Conflicting create/restore/recovery attributes specified.
XJ081 | Invalid value '<value>' passed as parameter '<parameterName>' to method '<methodName>'
XJ085 | Stream has already been read and end-of-file reached and cannot be re-used.
XJ086 | This method cannot be invoked while the cursor is not on the insert row or if the concurrency of this ResultSet object is CONCUR_READ_ONLY.
XJ087 | Sum of position('<pos>') and length('<length>') is greater than the size of the LOB.
XJ088 | Invalid operation: wasNull() called with no data retrieved.
XJ090 | Invalid parameter: calendar is null.
XJ091 | Invalid argument: parameter index <indexNumber> is not an OUT or INOUT parameter.
XJ093 | Length of BLOB/CLOB, <number>, is too large. The length cannot exceed <number>.
XJ094 | This object is already closed.
XJ095 | An attempt to execute a privileged action failed.
XJ096 | A resource bundle could not be found in the <packageName> package for <value>
XJ097 | Cannot rollback or release a savepoint that was not created by this connection.
XJ098 | The auto-generated keys value <value> is invalid
XJ099 | The Reader/Stream object does not contain length characters
XJ100 | The scale supplied by the registerOutParameter method does not match with the setter method. Possible loss of precision!
XJ102 | Can not perform an insert at the current position.
XJ103 | Table name can not be null
XJ104 | Shared key length is invalid: <value>.
XJ105 | DES key has the wrong length, expected length <number>, got length <number>.
XJ106 | No such padding
XJ107 | Bad Padding
XJ108 | Illegal Block Size
XJ110 | Primary table name can not be null
XJ111 | Foreign table name can not be null
XJ112 | Security exception encountered, see next exception for details.
XJ113 | Unable to open file <fileName> : <error>
XJ114 | Invalid cursor name '<cursorName>'
XJ115 | Unable to open resultSet with requested holdability <value>.
XJ116 | No more than <number> commands may be added to a single batch.
XJ117 | Batching of queries not allowed by J2EE compliance.
XJ118 | Query batch requested on a non-query statement.
XJ121 | Invalid operation at current cursor position.
XJ122 | No updateXXX methods were called on this row.
XJ123 | This method must be called to update values in the current row or the insert row.
XJ124 | Column not updatable.
XJ125 | This method should only be called on ResultSet objects that are scrollable (type TYPE_SCROLL_INSENSITIVE).
XJ126 | This method should not be called on sensitive dynamic cursors.
XJ128 | Unable to unwrap for '<value>'
XJ200 | Exceeded maximum number of sections <value>
XJ202 | Invalid cursor name '<cursorName>'.
XJ203 | Cursor name '<cursorName>' is already in use
XJ204 | Unable to open result set with requested holdability <holdValue>.
XJ206 | SQL text '<value>' has no tokens.
XJ207 | executeQuery method can not be used for update.
XJ208 | Non-atomic batch failure. The batch was submitted, but at least one exception occurred on an individual member of the batch. Use getNextException() to retrieve the exceptions for specific batched elements.
XJ209 | The required stored procedure is not installed on the server.
XJ210 | The load module name for the stored procedure on the server is not found.
XJ211 | Non-recoverable chain-breaking exception occurred during batch processing. The batch is terminated non-atomically.
XJ212 | Invalid attribute syntax: <attributeSyntax>
XJ213 | The traceLevel connection property does not have a valid format for a number.
XJ214 | An IO Error occurred when calling free() on a CLOB or BLOB.
XJ215 | You cannot invoke other java.sql.Clob/java.sql.Blob methods after calling the free() method or after the Blob/Clob's transaction has been committed or rolled back.
XJ216 | The length of this BLOB/CLOB is not available yet. When a BLOB or CLOB is accessed as a stream, the length is not available until the entire stream has been processed.
XJ217 | The locator that was supplied for this CLOB/BLOB is invalid

Table 70. Class XK: Security Exceptions

SQLSTATE | Message Text
XK000 | The security policy could not be reloaded: <reason>

Table 71. Class XN: Network Client Exceptions

SQLSTATE | Message Text
XN001 | Connection reset is not allowed when inside a unit of work.
XN008 | Query processing has been terminated due to an error on the server.
XN009 | Error obtaining length of BLOB/CLOB object, exception follows.
XN010 | Procedure name can not be null.
XN011 | Procedure name length <number> is not within the valid range of 1 to <number>.
XN012 | On <operatingSystemName> platforms, XA supports version <versionNumber> and above, this is version <versionNumber>
XN013 | Invalid scroll orientation.
XN014 | Network protocol error: encountered an IOException, parameter #<value>. Remaining data has been padded with 0x0. Message: <messageText>.
XN015 | Network protocol error: the specified size of the InputStream, parameter #<value>, is less than the actual InputStream length.
XN016 | Network protocol error: encountered error in stream length verification, parameter #<value>. Message: <messageText>.
XN017 | Network protocol error: end of stream prematurely reached, parameter #<value>. Remaining data has been padded with 0x0.
XN018 | Network protocol error: the specified size of the Reader, parameter #<value>, is less than the actual InputStream length.
XN019 | Error executing a <value>, server returned <value>.

Table 72. Class XSAI: Store - access.protocol.interface

SQLSTATE | Message Text
XSAI2 | The conglomerate (<value>) requested does not exist.
XSAI3 | Feature not implemented.

Table 73. Class XSAM: Store - AccessManager

SQLSTATE | Message Text
XSAM0 | Exception encountered while trying to boot module for '<value>'.
XSAM2 | There is no index or conglomerate with conglom id '<conglomID>' to drop.
XSAM3 | There is no index or conglomerate with conglom id '<conglomID>'.
XSAM4 | There is no sort called '<sortName>'.
XSAM5 | Scan must be opened and positioned by calling next() before making other calls.
XSAM6 | Record <containerName> on page <pageNumber> in container <recordNumber> not found.

Table 74. Class XSAS: Store - Sort

SQLSTATE | Message Text
XSAS0 | A scan controller interface method was called which is not appropriate for a scan on a sort.
XSAS1 | An attempt was made to fetch a row before the beginning of a sort or after the end of a sort.
XSAS3 | The type of a row inserted into a sort does not match the sort's template.
XSAS6 | Could not acquire resources for sort.

Table 75. Class XSAX: Store - access.protocol.XA statement

SQLSTATE | Message Text
XSAX0 | XA protocol violation.
XSAX1 | An attempt was made to start a global transaction with an Xid of an existing global transaction.

Table 76. Class XSCB: Store - BTree

SQLSTATE | Message Text
XSCB0 | Could not create container.
XSCB1 | Container <containerName> not found.
XSCB2 | The required property <propertyName> not found in the property list given to createConglomerate() for a btree secondary index.
XSCB3 | Unimplemented feature.
XSCB4 | A method on a btree open scan has been called prior to positioning the scan on the first row (i.e. no next() call has been made yet). The current state of the scan is (<value>).
XSCB5 | During logical undo of a btree insert or delete the row could not be found in the tree.
XSCB6 | Limitation: Record of a btree secondary index cannot be updated or inserted due to lack of space on the page. Use the parameters derby.storage.pageSize and/or derby.storage.pageReservedSpace to work around this limitation.
XSCB7 | An internal error was encountered during a btree scan - current_rh is null = <value>, position key is null = <value>.
XSCB8 | The btree conglomerate <value> is closed.
XSCB9 | Reserved for testing.

Table 77. Class XSCG0: Conglomerate

SQLSTATE | Message Text
XSCG0 | Could not create a template.

Table 78. Class XSCH: Heap

SQLSTATE | Message Text
XSCH0 | Could not create container.
XSCH1 | Container <containerName> not found.
XSCH4 | Conglomerate could not be created.
XSCH5 | In a base table there was a mismatch between the requested column number <number> and the maximum number of columns <number>.
XSCH6 | The heap container with container id <containerID> is closed.
XSCH7 | The scan is not positioned.
XSCH8 | The feature is not implemented.

Table 79. Class XSDA: RawStore - Data.Generic statement

SQLSTATE | Message Text
XSDA1 | An attempt was made to access an out of range slot on a page
XSDA2 | An attempt was made to update a deleted record
XSDA3 | Limitation: Record cannot be updated or inserted due to lack of space on the page. Use the parameters derby.storage.pageSize and/or derby.storage.pageReservedSpace to work around this limitation.
XSDA4 | An unexpected exception was thrown
XSDA5 | An attempt was made to undelete a record that is not deleted
XSDA6 | Column <columnName> of row is null, it needs to be set to point to an object.
XSDA7 | Restore of a serializable or SQLData object of class <className>, attempted to read more data than was originally stored
XSDA8 | Exception during restore of a serializable or SQLData object of class <className>
XSDA9 | Class not found during restore of a serializable or SQLData object of class <className>
XSDAA | Illegal time stamp <value>, either time stamp is from a different page or of incompatible implementation
XSDAB | cannot set a null time stamp
XSDAC | Attempt to move either rows or pages from one container to another.
XSDAD | Attempt to move zero rows from one page to another.
XSDAE | Can only make a record handle for special record handle id.
XSDAF | Using special record handle as if it were a normal record handle.
XSDAG | The allocation nested top transaction cannot open the container.
XSDAI | Page <page> being removed is already locked for deallocation.
XSDAJ | Exception during write of a serializable or SQLData object
XSDAK | Wrong page is gotten for record handle <value>.
XSDAL | Record handle <value> unexpectedly points to overflow page.
XSDAM | Exception during restore of a SQLData object of class <className>. The specified class cannot be instantiated.
XSDAN | Exception during restore of a SQLData object of class <className>. The specified class encountered an illegal access exception.

Table 80. Class XSDB: RawStore - Data.Generic transaction

SQLSTATE | Message Text
XSDB0 | Unexpected exception on in-memory page <page>
XSDB1 | Unknown page format at page <page>
XSDB2 | Unknown container format at container <containerName> : <value>
XSDB3 | Container information cannot change once written: was <value>, now <value>
XSDB4 | Page <page> is at version <versionNumber>, the log file contains change version <versionNumber>, either there are log records of this page missing, or this page did not get written out to disk properly.
XSDB5 | Log has change record on page <page>, which is beyond the end of the container.
XSDB6 | Another instance of Derby may have already booted the database <databaseName>.
XSDB7 | WARNING: Derby (instance <value>) is attempting to boot the database <databaseName> even though Derby (instance <value>) may still be active. Only one instance of Derby should boot a database at a time. Severe and non-recoverable corruption can result and may have already occurred.
XSDB8 | WARNING: Derby (instance <value>) is attempting to boot the database <databaseName> even though Derby (instance <value>) may still be active. Only one instance of Derby should boot a database at a time. Severe and non-recoverable corruption can result if 2 instances of Derby boot on the same database at the same time. The db2j.database.forceDatabaseLock=true property has been set, so the database will not boot until the db.lck is no longer present. Normally this file is removed when the first instance of Derby to boot on the database exits, but it may be left behind in some shutdowns. It will be necessary to remove the file by hand in that case. It is important to verify that no other VM is accessing the database before deleting the db.lck file by hand.
XSDB9 | Stream container <containerName> is corrupt.
XSDBA | Attempt to allocate object <object> failed.

Table 81. Class XSDF: RawStore - Data.Filesystem statement

SQLSTATE | Message Text
XSDF0 | Could not create file <fileName> as it already exists.
XSDF1 | Exception during creation of file <fileName> for container
XSDF2 | Exception during creation of file <fileName> for container, file could not be removed. The exception was: <value>.
XSDF3 | Cannot create segment <segmentName>.
XSDF4 | Exception during remove of file <fileName> for dropped container, file could not be removed <value>.
XSDF6 | Cannot find the allocation page <page>.
XSDF7 | Newly created page failed to be latched <value>
XSDF8 | Cannot find page <page> to reuse.
XSDFB | Operation not supported by a read only database
XSDFD | Different page image read on 2 I/Os on Page <page>, first image has incorrect checksum, second image has correct checksum. Page images follows: <value><value>
XSDFF | The requested operation failed due to an unexpected exception.
XSDFH | Cannot backup the database, got an I/O Exception while writing to the backup container file <fileName>.
XSDFI | Error encountered while trying to write data to disk during database recovery. Check that the database disk is not full. If it is then delete unnecessary files, and retry connecting to the database. It is also possible that the file system is read only, or the disk has failed, or some other problem with the media. System encountered error while processing page <page>.

Table 82. Class XSDG: RawStore - Data.Filesystem database

SQLSTATE | Message Text
XSDG0 | Page <page> could not be read from disk.
XSDG1 | Page <page> could not be written to disk, please check if disk is full.
XSDG2 | Invalid checksum on Page <page>, expected=<value>, on-disk version=<value>, page dump follows: <value>
XSDG3 | Meta-data for Container <containerName> could not be accessed
XSDG5 | Database is not in create mode when createFinished is called.
XSDG6 | Data segment directory not found in <value> backup during restore. Please make sure that backup copy is the right one and it is not corrupted.
XSDG7 | Directory <directoryName> could not be removed during restore. Please make sure that permissions are correct.
XSDG8 | Unable to copy directory '<directoryName>' to '<value>' during restore. Please make sure that there is enough space and permissions are correct.

Table 83. Class XSLA: RawStore - Log.Generic database exceptions

SQLSTATE | Message Text
XSLA0 | Cannot flush the log file to disk <value>.
XSLA1 | Log Record has been sent to the stream, but it cannot be applied to the store (Object <object>). This may cause recovery problems also.
XSLA2 | System will shutdown, got I/O Exception while accessing log file.
XSLA3 | Log Corrupted, has invalid data in the log stream.
XSLA4 | Cannot write to the log, most likely the log is full. Please delete unnecessary files. It is also possible that the file system is read only, or the disk has failed, or some other problems with the media.
XSLA5 | Cannot read log stream for some reason to rollback transaction <transactionID>.
XSLA6 | Cannot recover the database.
XSLA7 | Cannot redo operation <operation> in the log.
XSLA8 | Cannot rollback transaction <value>, trying to compensate <value> operation with <value>
XSLAA | The store has been marked for shutdown by an earlier exception.
XSLAB | Cannot find log file <logfileName>, please make sure your logDevice property is properly set with the correct path separator for your platform.
XSLAC | Database at <value> have incompatible format with the current version of software, it may have been created by or upgraded by a later version.
XSLAD | log Record at instant <value> in log file <value> corrupted. Expected log record length <value>, real length <logfileName>.
XSLAE | Control file at <value> cannot be written or updated.
XSLAF | A Read Only database was created with dirty data buffers.
XSLAH | A Read Only database is being updated.
XSLAI | Cannot log the checkpoint log record
XSLAJ | The logging system has been marked to shut down due to an earlier problem and will not allow any more operations until the system shuts down and restarts.
XSLAK | Database has exceeded largest log file number <value>.
XSLAL | log record size <logfileName> exceeded the maximum allowable log file size <value>. Error encountered in log file <value>, position <number>.
XSLAM | Cannot verify database format at {1} due to IOException.
XSLAN | Database at <value> has an incompatible format with the current version of the software. The database was created by or upgraded by version <versionNumber>.
XSLAO | Recovery failed unexpected problem <value>.
XSLAP | Database at <value> is at version <versionNumber>. Beta databases cannot be upgraded,
XSLAQ | cannot create log file at directory <directoryName>.
XSLAR | Unable to copy log file '<logfileName>' to '<value>' during restore. Please make sure that there is enough space and permissions are correct.
XSLAS | Log directory <directoryName> not found in backup during restore. Please make sure that backup copy is the correct one and it is not corrupted.
XSLAT | The log directory '<directoryName>' exists. The directory might belong to another database. Check that the location specified for the logDevice attribute is correct.

Table 84. Class XSLB: RawStore - Log.Generic statement exceptions

SQLSTATE | Message Text
XSLB1 | Log operation <logOperation> encounters error writing itself out to the log stream, this could be caused by an errant log operation or internal log buffer full due to excessively large log operation.
XSLB2 | Log operation <logOperation> logging excessive data, it filled up the internal log buffer.
XSLB4 | Cannot find truncationLWM <value>.
XSLB5 | Illegal truncationLWM instant <value> for truncation point <value>. Legal range is from <value> to <value>.
XSLB6 | Trying to log a 0 or -ve length log Record.
XSLB8 | Trying to reset a scan to <value>, beyond its limit of <value>.
XSLB9 | Cannot issue any more change, log factory has been stopped.

Table 85. Class XSRS: RawStore - protocol.Interface statement

SQLSTATE | Message Text
XSRS0 | Cannot freeze the database after it is already frozen.
XSRS1 | Cannot backup the database to <value>, which is not a directory.
XSRS4 | Error renaming file (during backup) from <value> to <value>.
XSRS5 | Error copying file (during backup) from <path> to <path>.
XSRS6 | Cannot create backup directory <directoryName>.
XSRS7 | Backup caught unexpected exception.
XSRS8 | Log Device can only be set during database creation time, it cannot be changed on the fly.
XSRS9 | Record <recordName> no longer exists
XSRSA | Cannot backup the database when unlogged operations are uncommitted. Please commit the transactions with backup blocking operations.
XSRSB | Backup cannot be performed in a transaction with uncommitted unlogged operations.
XSRSC | Cannot backup the database to <directoryLocation>, it is a database directory.

Table 86. Class XSTA2: XACT_TRANSACTION_ACTIVE

SQLSTATE | Message Text
XSTA2 | A transaction was already active, when attempt was made to make another transaction active.

Table 87. Class XSTB: RawStore - Transactions.Basic system

SQLSTATE | Message Text
XSTB0 | An exception was thrown during transaction abort.
XSTB2 | Cannot log transaction changes, maybe trying to write to a read only database.
XSTB3 | Cannot abort transaction because the log manager is null, probably due to an earlier error.
XSTB5 | Creating database with logging disabled encountered unexpected problem.
XSTB6 | Cannot substitute a transaction table with another while one is already in use.

Table 88. Class XXXXX: No SQLSTATE

SQLSTATE | Message Text
XXXXX | Normal database session close.

JDBC reference
Derby comes with a built-in JDBC driver.
That makes the JDBC API the only API for working with Derby databases. The driver is a native protocol all-Java driver (type number four of types defined by Sun).
This section provides reference information about Derby's implementation of the JDBC API and documents the way it conforms to the JDBC 2.0, 3.0, and 4.0 APIs.
See the Java DB Developer's Guide for task-oriented instructions on working with the driver.
This JDBC driver implements the standard JDBC interface defined by Sun. When invoked from an application running in the same JVM as Derby, the JDBC driver supports connections to a Derby database in embedded mode. No network transport is required to access the database. In client/server mode, the client application dispatches JDBC requests to the JDBC server over a network; the server, in turn, which runs in the same JVM as Derby, sends requests to Derby through the embedded JDBC driver.
The Derby JDBC implementation provides access to Derby databases and supplies all the required JDBC interfaces. Unimplemented aspects of the JDBC driver return an SQLException with a message stating "Feature not implemented" and an SQLState of XJZZZ. These unimplemented parts are for features not supported by Derby.
Core JDBC java.sql classes, interfaces, and methods
This section details Derby's implementation of the following java.sql classes, interfaces, and methods:

• |  | java.sql.Driver interface
• |  | java.sql.DriverManager.getConnection method
• |  | java.sql.Driver.getPropertyInfo method
• |  | java.sql.Connection interface
• |  | java.sql.DatabaseMetaData interface
• |  | java.sql.Statement interface
• |  | java.sql.PreparedStatement interface
• |  | java.sql.CallableStatement interface
• |  | java.sql.ResultSet interface
• |  | java.sql.ResultSetMetaData interface
• |  | java.sql.SQLException class
• |  | java.sql.SQLWarning class
• |  | Mapping of java.sql.Types to SQL types

java.sql.Driver interface
The class that loads Derby's local JDBC driver is the class org.apache.derby.jdbc.EmbeddedDriver. Listed below are some of the ways to create instances of that class. Do not use the class directly through the java.sql.Driver interface. Use the DriverManager class to create connections.

• |  | If your application runs on JDK 1.6 or higher, you do not need to do any of the following. The EmbeddedDriver will load automatically when your application asks for its first Connection.
• |  | Class.forName("org.apache.derby.jdbc.EmbeddedDriver") Our recommended manner, because it ensures that the class is loaded in all JVMs by creating an instance at the same time.
• |  | new org.apache.derby.jdbc.EmbeddedDriver() Same as Class.forName("org.apache.derby.jdbc.EmbeddedDriver"), except that it requires the class to be found when the code is compiled.
• |  | Class c = org.apache.derby.jdbc.EmbeddedDriver.class This is also the same as Class.forName("org.apache.derby.jdbc.EmbeddedDriver"), except that it requires the class to be found when the code is compiled. The pseudo-static field class evaluates to the class that is named.
• |  | Setting the System property jdbc.drivers To set a System property, you alter the invocation command line or the system properties within your application. It is not possible to alter system properties within an applet.

    java -Djdbc.drivers=org.apache.derby.jdbc.EmbeddedDriver
        applicationClass

The actual driver that gets registered in the DriverManager to handle the jdbc:derby: protocol is not the class org.apache.derby.jdbc.EmbeddedDriver; that class simply detects the type of Derby driver needed and then causes the appropriate Derby driver to be loaded.
The only supported way to connect to a Derby system through the jdbc:derby: protocol is using the DriverManager to obtain a driver (java.sql.Driver) or connection (java.sql.Connection) through the getDriver and getConnection method calls.
java.sql.Driver.getPropertyInfo method
To get the DriverPropertyInfo object, request the JDBC driver from the driver manager:

    java.sql.DriverManager.getDriver("jdbc:derby:").
        getPropertyInfo(URL, Prop)

Do not request it from org.apache.derby.jdbc.EmbeddedDriver, which is only an intermediary class that loads the actual driver.
This method might return a DriverPropertyInfo object. In a Derby system, it consists of an array of database connection URL attributes. The most useful attribute is databaseName=nameofDatabase, which means that the object consists of a list of booted databases in the current system.
For example, if a Derby system has the databases toursDB and flightsDB in its system directory, all the databases in the system are set to boot automatically, and a user has also connected to a database A:/dbs/tours94, the array returned from getPropertyInfo contains one object corresponding to the databaseName attribute. The choices field of the DriverPropertyInfo object will contain an array of three Strings with the values toursDB, flightsDB, and A:/dbs/tours94. Note that this object is returned only if the proposed connection objects do not already include a database name (in any form) or include the shutdown attribute with the value true.
For more information about java.sql.Driver.getPropertyInfo, see "Offering connection choices to the user" in the Java DB Developer's Guide.
java.sql.DriverManager.getConnection method
A Java application using the JDBC API establishes a connection to a database by obtaining a Connection object. The standard way to obtain a Connection object is to call the method DriverManager.getConnection, which takes a String containing a database connection URL. A JDBC database connection URL (uniform resource locator) provides a way of identifying a database.
DriverManager.getConnection can take one argument besides a database connection URL, a Properties object. You can use the Properties object to set database connection URL attributes.
You can also supply strings representing user names and passwords. When they are supplied, Derby checks whether they are valid for the current system if user authentication is enabled. User names are passed to Derby as authorization identifiers, which are used to determine whether the user is authorized for access to the database and for determining the default schema. When the connection is established, if no user is supplied, Derby sets the default user to APP, which Derby uses to name the default schema. If a user is supplied, the default schema is the same as the user name.
Derby database connection URL syntax
A Derby database connection URL consists of the basic database connection URL followed by an optional subsubprotocol and optional attributes.
This section provides reference information only. For a more complete description, including examples, see "Connecting to Databases" in Chapter 1 of the Java DB Developer's Guide.
Syntax of database connection URLs for applications with embedded databases
For applications with embedded databases, the syntax of the database connection URL is

    jdbc:derby: [subsubprotocol:][databasename][;attributes]*

• |  | jdbc:derby: In JDBC lingo, derby is the subprotocol for connecting to a Derby database. The subprotocol is always derby and does not vary.
• |  | subsubprotocol: subsubprotocol, which is not typically specified, specifies where Derby looks for a database: in a directory, in a classpath, or in a jar file. It is used only in rare instances, usually for read-only databases. subsubprotocol is one of the following:
• |  | directory
• |  | classpath: Databases are treated as read-only databases, and all databaseNames must begin with at least a slash, because you specify them "relative" to the classpath directory or archive. (You do not have to specify classpath as the subsubprotocol; it is implied.)
• |  | jar Databases are treated as read-only databases.
jar: requires an additional element immediately before the databaseName:
    (pathToArchive)
pathToArchive is the path to the jar or zip file that holds the database and includes the name of the jar or zip file. See the Java DB Developer's Guide for examples of database connection URLs for read-only databases.
• |  | databaseName Specify the databaseName to connect to an existing database or a new one. You can specify the database name alone, or with a relative or absolute path. See "Standard Connections-Connecting to Databases in the File System" in Chapter 1 of the Java DB Developer's Guide.
• |  | attributes Specify 0 or more database connection URL attributes as detailed in Attributes of the Derby database connection URL.

Additional SQL syntax
Derby also supports the following SQL standard syntax to obtain a reference to the current connection in a database-side JDBC procedure or method:

    jdbc:default:connection

Attributes of the Derby database connection URL
You can supply an optional list of attributes to a database connection URL. Derby translates these attributes into properties, so you can also set attributes in a Properties object passed to DriverManager.getConnection. (You cannot set those attributes as system properties, only in an object passed to the DriverManager.getConnection method.)
These attributes are specific to Derby and are listed in Setting attributes for the database connection URL.
Attribute name/value pairs are converted into properties and added to the properties provided in the connection call. If no properties are provided in the connection call, a properties set is created that contains only the properties obtained from the database connection URL.

    import java.util.Properties;

    Connection conn = DriverManager.getConnection(
        "jdbc:derby:sampleDB;create=true");

    /* setting an attribute in a Properties object */
    Properties myProps = new Properties();
    myProps.put("create", "true");
    Connection conn = DriverManager.getConnection(
        "jdbc:derby:sampleDB", myProps);

    /* passing user name and password */
    Connection conn = DriverManager.getConnection(
        "jdbc:derby:sampleDB", "dba", "password");

Note: Attributes are not parsed for correctness. If you pass in an incorrect attribute or corresponding value, it is simply ignored. (Derby does provide a tool for parsing the correctness of attributes. For more information, see the Java DB Tools and Utilities Guide.)
java.sql.Connection interface
A DerbyConnection object is not garbage-collected until all other JDBC objects created from that connection are explicitly closed or are themselves garbage-collected. Once the connection is closed, no further JDBC requests can be made against objects created from the connection. Do not explicitly close the Connection object until you no longer need it for executing statements.
A session-severity or higher exception causes the connection to close and all other JDBC objects against it to be closed. System-severity exceptions cause the Derby system to shut down, which not only closes the connection but means that no new connections should be created in the current JVM.
java.sql.Connection.setTransactionIsolation method
java.sql.Connection.TRANSACTION_SERIALIZABLE, java.sql.Connection.TRANSACTION_REPEATABLE_READ, java.sql.Connection.TRANSACTION_READ_COMMITTED, and java.sql.Connection.TRANSACTION_READ_UNCOMMITTED transaction isolations are available from a Derby database.
TRANSACTION_READ_COMMITTED is the default isolation level.
Changing the current isolation for the connection with setTransactionIsolation commits the current transaction and begins a new transaction. For more details about transaction isolation, see "Locking, concurrency, and isolation" in the Java DB Developer's Guide.
java.sql.Connection.setReadOnly method
java.sql.Connection.setReadOnly is supported.
See the section "Differences using the Connection.setReadOnly method" in the Java DB Server and Administration Guide for more information.
java.sql.Connection.isReadOnly method
If you connect to a read-only database, the appropriate isReadOnly DatabaseMetaData value is returned. For example, Connections set to read-only using the setReadOnly method, Connections for which the user has been defined as a readOnlyAccess user (with one of the Derby properties), and Connections to databases on read-only media return true.
Connection functionality not supported
Derby does not use catalog names. In addition, the following optional methods raise "Feature not supported" exceptions:

• |  | createArrayOf( java.lang.String, java.lang.Object[] )
• |  | createNClob( )
• |  | createSQLXML( )
• |  | createStruct( java.lang.String, java.lang.Object[] )
• |  | getTypeMap( )
• |  | prepareStatement( java.lang.String, int[] )
• |  | prepareStatement( java.lang.String, java.lang.String[] )
• |  | setTypeMap( java.util.Map )

java.sql.DatabaseMetaData interface
This section discusses java.sql.DatabaseMetaData functionality in Derby.
DatabaseMetaData result sets
DatabaseMetaData result sets do not close the result sets of other statements, even when auto-commit is set to true.
DatabaseMetaData result sets are closed if a user performs any other action on a JDBC object that causes an automatic commit to occur. If you need the DatabaseMetaData result sets to be accessible while executing other actions that would cause automatic commits, turn off auto-commit with setAutoCommit(false).
java.sql.DatabaseMetaData.getProcedureColumns method
Derby supports Java procedures. Derby allows you to call Java procedures within SQL statements. Derby returns information about the parameters in the getProcedureColumns call. If the corresponding Java method is overloaded, it returns information about each signature separately. Derby returns information for all Java procedures defined by CREATE PROCEDURE.
getProcedureColumns returns a ResultSet. Each row describes a single parameter or return value.
Parameters to getProcedureColumns
The JDBC API defines the following parameters for this method call:

• |  | catalog always use null for this parameter in Derby.
• |  | schemaPattern Java procedures have a schema.
• |  | procedureNamePattern a String object representing a procedure name pattern.
• |  | column-Name-Pattern a String object representing the name pattern of the parameter names or return value names. Java procedures have parameter names matching those defined in the CREATE PROCEDURE statement. Use "%" to find all parameter names.

Columns in the ResultSet returned by getProcedureColumns
Columns in the ResultSet returned by getProcedureColumns are as described by the API. Further details for some specific columns:

• |  | PROCEDURE_CAT always "null" in Derby
• |  | PROCEDURE_SCHEM schema for a Java procedure
• |  | PROCEDURE_NAME the name of the procedure
• |  | COLUMN_NAME the name of the parameter (see column-Name-Pattern)
• |  | COLUMN_TYPE short indicating what the row describes. Always is DatabaseMetaData.procedureColumnIn for method parameters, unless the parameter is an array. If so, it is DatabaseMetaData.procedureColumnInOut. It always returns DatabaseMetaData.procedureColumnReturn for return values.
• |  | TYPE_NAME Derby-specific name for the type.
• |  | NULLABLE always returns DatabaseMetaData.procedureNoNulls for primitive parameters and DatabaseMetaData.procedureNullable for object parameters
• |  | REMARKS a String describing the java type of the method parameter
• |  | COLUMN_DEF a String describing the default value for the column (may be null)
• |  | SQL_DATA_TYPE reserved by JDBC spec for future use
• |  | SQL_DATETIME_SUB reserved by JDBC spec for future use
• |  | CHAR_OCTET_LENGTH the maximum length of binary and character based columns (or any other datatype the returned value is a NULL)
• |  | ORDINAL_POSITION the ordinal position, starting from 1, for the input and output parameters for a procedure.
• |  | IS_NULLABLE a String describing the parameter's nullability (YES means parameter can include NULLs, NO means it can't)
• |  | SPECIFIC_NAME the name which uniquely identifies this procedure within its schema
• |  | METHOD_ID a Derby-specific column.
• |  | PARAMETER_ID a Derby-specific column.

java.sql.DatabaseMetaData.getBestRowIdentifier method
The java.sql.DatabaseMetaData.getBestRowIdentifier method looks for identifiers in a specific order. This order might not return a unique row.
The java.sql.DatabaseMetaData.getBestRowIdentifier method looks for identifiers in the following order:

• |  | A primary key on the table
• |  | A unique constraint or unique index on the table
• |  | All of the columns in the table

Note: If the java.sql.DatabaseMetaData.getBestRowIdentifier method does not find a primary key, unique constraint, or unique index, the method must look for identifiers in all of the columns in the table. When the method looks for identifiers this way, the method will always find a set of columns that identify a row. However, a unique row might not be identified if there are duplicate rows in the table.
java.sql.Statement interface
Derby does not implement the JDBC 1.2 setEscapeProcessing method of java.sql.Statement. In addition, the following optional methods raise "Feature not supported" exceptions:

• |  | cancel( )
• |  | execute( java.lang.String, int[] )
• |  | execute( java.lang.String, String[] )
• |  | executeUpdate( java.lang.String, int[] )
• |  | executeUpdate( java.lang.String, String[] )

ResultSet objects
An error that occurs when a SELECT statement is first executed prevents a ResultSet object from being opened on it. The same error does not close the ResultSet if it occurs after the ResultSet has been opened.
For example, a divide-by-zero error that happens while the executeQuery method is called on a java.sql.Statement or java.sql.PreparedStatement throws an exception and returns no result set at all, while if the same error happens while the next method is called on a ResultSet object, it does not cause the result set to be closed.
Errors can happen when a ResultSet is first being created if the system partially executes the query before the first row is fetched. This can happen on any query that uses more than one table and on queries that use aggregates, GROUP BY, ORDER BY, DISTINCT, INTERSECT, EXCEPT, or UNION.
Closing a Statement causes all open ResultSet objects on that statement to be closed as well.
The cursor name for the cursor of a ResultSet can be set before the statement is executed. However, once it is executed, the cursor name cannot be altered.
java.sql.CallableStatement interface
Derby supports all the JDBC 1.2 methods of CallableStatement:

• |  | getBoolean()
• |  | getByte()
• |  | getBytes()
• |  | getDate()
• |  | getDouble()
• |  | getFloat()
• |  | getInt()
• |  | getLong()
• |  | getObject()
• |  | getShort()
• |  | getString()
• |  | getTime()
• |  | getTimestamp()
• |  | registerOutParamter()
• |  | wasNull()

CallableStatements and OUT Parameters
Derby supports OUT parameters and CALL statements that return values, as in the following example:

    CallableStatement cs = conn.prepareCall(
       "? = CALL getDriverType(cast (? as INT))"
    cs.registerOutParameter(1, Types.INTEGER);
    cs.setInt(2, 35);
    cs.executeUpdate();

Note: Using a CALL statement with a procedure that returns a value is only supported with the ? = syntax.
Register the output type of the parameter before executing the call.
CallableStatements and INOUT Parameters
INOUT parameters map to an array of the parameter type in Java. (The method must take an array as its parameter.) This conforms to the recommendations of the SQL standard.
Given the following example:

    CallableStatement call = conn.prepareCall(
        "{CALL doubleMyInt(?)}");
    // for inout parameters, it is good practice to
    // register the outparameter before setting the input value
    call.registerOutParameter(1, Types.INTEGER);
    call.setInt(1,10);
    call.execute();
    int retval = call.getInt(1);

The method doubleIt should take a one-dimensional array of ints. Here is sample source code for that method:

    public static void doubleMyInt(int[] i) {
        i[0] *=2;
        /* Derby  returns the first element of the array.*/
    }

Note: The return value is not wrapped in an array even though the parameter to the method is.
Table 89. INOUT Parameter Type Correspondence

JDBC Type | Array Type for Method Parameter | Value and Return Type
BIGINT | long[] | long
BINARY | byte[][] | byte[]
BIT | boolean[] | boolean
DATE | java.sql.Date[] | java.sql.Date
DOUBLE | double[] | double
FLOAT | double[] | double
INTEGER | int[] | int
LONGVARBINARY | byte[][] | byte[]
REAL | float[] | float
SMALLINT | short[] | short
TIME | java.sql.Time[] | java.sql.Time
TIMESTAMP | java.sql.Timestamp[] | java.sql.Timestamp
VARBINARY | byte[][] | byte[]
OTHER | yourType[] | yourType
JAVA_OBJECT (only valid in Java2/JDBC 2.0 environments) | yourType[] | yourType

Register the output type of the parameter before executing the call. For INOUT parameters, it is good practice to register the output parameter before setting its input value.
java.sql.SQLException class
Derby supplies values for the getMessage(), getSQLState(), and getErrorCode() calls of SQLExceptions. In addition, Derby sometimes returns multiple SQLExceptions using the nextException chain. The first exception is always the most severe exception, with SQL-92 Standard exceptions preceding those that are specific to Derby. For information on processing SQLExceptions, see "Working with Derby SQLExceptions in an application" in the Java DB Developer's Guide.
java.sql.PreparedStatement interface
Derby provides all the required JDBC 1.2 type conversions and additionally allows use of the individual setXXX methods for each type as if a setObject(Value, JDBCTypeCode) invocation were made.
This means that setString can be used for any built-in target type.
The setCursorName method can be used on a PreparedStatement prior to an execute request to control the cursor name used when the cursor is created.
Prepared statements and streaming columns
setXXXStream requests stream data between the application and the database.
JDBC allows an IN parameter to be set to a Java input stream for passing in large amounts of data in smaller chunks. When the statement is executed, the JDBC driver makes repeated calls to this input stream, reading its contents and transmitting those contents as the parameter data.
Derby supports the three types of streams that JDBC 1.2 provides. These three streams are:

• |  | setBinaryStream for streams containing uninterpreted bytes
• |  | setAsciiStream for streams containing ASCII characters
• |  | setUnicodeStream for streams containing Unicode characters

JDBC 2.0 and JDBC 3.0 require that you specify the length of the stream and Derby enforces this requirement if your application runs on JDK 1.5 or earlier. If your application runs on JDK 1.6, then Derby exposes a JDBC 4.0 implementation, which lets you use the streaming interfaces without having to specify the stream length. The stream object passed to these three methods can be either a standard Java stream object or the user's own subclass that implements the standard java.io.InputStream interface.
According to the JDBC standard, streams can be stored only in columns of the data types shown in Streamable JDBC Data Types. Streams cannot be stored in columns of the other built-in data types or of user-defined data types.
Table 90. Streamable JDBC Data Types

Column Values | Type Correspondent | AsciiStream | UnicodeStream | BinaryStream
CLOB | java.sql.Clob | x | x | '
CHAR | ' | x | x | '
VARCHAR | ' | x | x | '
LONGVARCHAR | ' | X | X | '
BINARY | ' | x | x | x
BLOB | java.sql.Blob | x | x | x
VARBINARY | ' | x | x | x
LONGVARBINARY | ' | x | x | X

A large X indicates the preferred target data type for the type of stream. (See Mapping of java.sql.Types to SQL Types.)
Note: If the stream is stored in a column of a type other than LONG VARCHAR or LONG VARCHAR FOR BIT DATA, the entire stream must be able to fit into memory at one time. Streams stored in LONG VARCHAR and LONG VARCHAR FOR BIT DATA columns do not have this limitation.
The following example shows how a user can store a streamed java.io.File in a LONG VARCHAR column:

    Statement s = conn.createStatement();
    s.executeUpdate("CREATE TABLE atable (a INT, b LONG VARCHAR)");
    conn.commit();
    java.io.File file = new java.io.File("derby.txt");
    int fileLength = (int) file.length();
    // first, create an input stream
    java.io.InputStream fin = new java.io.FileInputStream(file);
    PreparedStatement ps = conn.prepareStatement(
        "INSERT INTO atable VALUES (?, ?)");
    ps.setInt(1, 1);
    // set the value of the input parameter to the input stream
    ps.setAsciiStream(2, fin, fileLength);
    ps.execute();
    conn.commit();

java.sql.ResultSet interface
A positioned update or delete issued against a cursor being accessed through a ResultSet object modifies or deletes the current row of the ResultSet object.
Some intermediate protocols might pre-fetch rows. This causes positioned updates and deletes to operate against the row the underlying cursor is on, and not the current row of the ResultSet.
Derby provides all the required JDBC 1.2 type conversions of the getXXX methods.
JDBC does not define the sort of rounding to use for ResultSet.getBigDecimal. Derby uses java.math.BigDecimal.ROUND_HALF_DOWN.
ResultSets and streaming columns
If the underlying object is itself an OutputStream class, getBinaryStream returns the object directly.
To get a field from the ResultSet using streaming columns, you can use the getXXXStream methods if the type supports it. See Streamable JDBC Data Types for a list of types that support the various streams. (See also Mapping of java.sql.Types to SQL Types.)
You can retrieve data from one of the supported data type columns as a stream, whether or not it was stored as a stream.
The following example shows how a user can retrieve a LONG VARCHAR column as a stream:

    // retrieve data as a stream
    ResultSet rs = s.executeQuery("SELECT b FROM atable");
    while (rs.next()) {
        // use a java.io.InputStream to get the data
        java.io.InputStream ip = rs.getAsciiStream(1);
        // process the stream--this is just a generic way to// print the data
        int c;
        int columnSize = 0;
        byte[] buff = new byte[128];
        for (;;) {
            int size = ip.read(buff);
            if (size == -1)
                break;
            columnSize += size;
            String chunk = new String(buff, 0, size);
            System.out.print(chunk);
        }
    }
    rs.close();
    s.close();
    conn.commit();

java.sql.ResultSetMetaData interface
Derby does not track the source or updatability of columns in ResultSets, and so always returns the following constants for the following methods:

Method Name | Value
isDefinitelyWritable | false
isReadOnly | false
isWritable | false

java.sql.SQLWarning class
Derby can generate a warning in certain circumstances. A warning is generated if, for example, you try to connect to a database with the create attribute set to true if the database already exists. Aggregates like sum() also raise a warning if NULL values are encountered during the evaluation.
All other informational messages are written to the Derby system's derby.log file.
java.sql.SQLXML interface
In JDBC 4.0, java.sql.SQLXML is the mapping for the SQL XML data type. However, Derby defines the XML data type and operators only in the SQL layer. There is no JDBC-side support for the XML data type and operators
You cannot instantiate a java.sql.SQLXML object in Derby, or bind directly into an XML value or retrieve an XML value directly from a result set. You must bind and retrieve the XML data as Java strings or character streams by explicitly specifying the XML operators, XMLPARSE and XMLSERIALIZE, as part of your SQL queries.
Additionally, Derby does not provide JDBC metatadata support for the XML data type.
Mapping of java.sql.Types to SQL types
In Derby, the java.sql.Types are mapped to SQL data types
The following table shows the mapping of java.sql.Types to SQL types.
Table 91. Mapping of java.sql.Types to SQL Types

java.sql.Types | SQL Types
BIGINT | BIGINT
BINARY | CHAR FOR BIT DATA
BIT1 | CHAR FOR BIT DATA
BLOB | BLOB (JDBC 2.0 and up)
CHAR | CHAR
CLOB | CLOB (JDBC 2.0 and up)
DATE | DATE
DECIMAL | DECIMAL
DOUBLE | DOUBLE PRECISION
FLOAT | DOUBLE PRECISION2
INTEGER | INTEGER
LONGVARBINARY | LONG VARCHAR FOR BIT DATA
LONGVARCHAR | LONG VARCHAR
NULL | Not a data type; always a value of a particular type
NUMERIC | DECIMAL
REAL | REAL
SMALLINT | SMALLINT
SQLXML3 | XML
TIME | TIME
TIMESTAMP | TIMESTAMP
VARBINARY | VARCHAR FOR BIT DATA
VARCHAR | VARCHAR

Notes:

1. |  | BIT is only valid in JDBC 2.0 and earlier environments.
2. |  | Values can be passed in using the FLOAT type code; however, these are stored as DOUBLE PRECISION values, and so always have the type code DOUBLE when retrieved.
3. |  | SQLXML is only valid in JDBC 4.0 and later environments. SQLXML corresponds to the SQL type XML in Derby. However, Derby does not recognize the java.sql.Types.SQLXML data type and does not support any JDBC-side operations for the XML data type. Support for XML and the related operators is implemented only at the SQL layer. See XML data types for more.

Mapping of java.sql.Blob and java.sql.Clob interfaces
In JDBC 2.0, java.sql.Blob is the mapping for the SQL BLOB (binary large object) type; java.sql.Clob is the mapping for the SQL CLOB (character large object) type.
java.sql.Blob and java.sql.Clob provide a logical pointer to the large object rather than a complete copy of the objects. Derby processes only one data page into memory at a time. The whole BLOB does not need to be processed and stored in memory just to access the first few bytes of the LOB object
Derby now supports the built-in BLOB or CLOB data types. Derby also provides the following support for these data types:

• |  | BLOB FeaturesDerby supports the java.sql.Blob interface and the BLOB-related methods listed in java.sql.PreparedStatement interface: supported JDBC 2.0 methods and java.sql.ResultSet interface: supported JDBC 2.0 methods. The getBlob methods of CallableStatement are not implemented.
• |  | CLOB FeaturesDerby supports the java.sql.Clob interface and the CLOB-related methods listed in java.sql.PreparedStatement interface: supported JDBC 2.0 methods and java.sql.ResultSet interface: supported JDBC 2.0 methods. The getClob methods of CallableStatement procedures are not implemented.

To use the java.sql.Blob and java.sql.Clob features:

• |  | Use the SQL BLOB type for storage; LONG VARCHAR FOR BIT DATA, BINARY, and VARCHAR FOR BIT DATA types also work.
• |  | Use the SQL CLOB type for storage; LONG VARCHAR, CHAR, and VARCHAR types also work.
• |  | Use the getBlob or getClob methods on the java.sql.ResultSet interface to retrieve a BLOB or CLOB handle to the underlying data.
• |  | You cannot call static methods on any LOB-columns.

In addition, casting between strings and BLOBs is not recommended because casting is platform and database dependent.
Derby uses unicode strings (2 byte characters), while other database products may use ASCII characters (1 byte per character). If various codepages are used, each character might need several bytes. A larger BLOB type might be necessary to accommodate a normal string in Derby. You should use CLOB types for storing strings.
Restrictions on BLOB, CLOB, (LOB-types):

• |  | LOB-types cannot be compared for equality(=) and non-equality(!=, <>.
• |  | LOB-typed values are not order-able, so <, <=, >, >= tests are not supported.
• |  | LOB-types cannot be used in indices or as primary key columns.
• |  | DISTINCT, GROUP BY, ORDER BY clauses are also prohibited on LOB-types.
• |  | LOB-types cannot be involved in implicit casting as other base-types.

Derby implements all of the methods for these JDBC 2.0 interfaces except for the set and get methods in CallableStatement interface.
Recommendations: Because the lifespan of a java.sql.Blob or java.sql.Clob ends when the transaction commits, turn off auto-commit with the java.sql.Blob or java.sql.Clob features.
Table 92. JDBC 2.0 java.sql.Blob Methods Supported

Returns | Signature | Implementation Notes
InputStream | getBinaryStream() | '
byte[] | getBytes(long pos, int length) | Exceptions are raised if pos < 1, if pos is larger than the length of the , or if length <= 0.
long | length() | '
long | position(byte[] pattern, long start) | Exceptions are raised if pattern == null, if start < 1, or if pattern is an array of length 0.
long | position(Blob pattern, long start) | Exceptions are raised if pattern == null, if start < 1, if pattern has length 0, or if an exception is thrown when trying to read the first byte of pattern.

Table 93. JDBC 2.0 java.sql.Clob Methods Supported

Returns | Signature | Implementation Notes
InputStream | getAsciiStream() | '
Reader | getCharacterStream() | '
String | getSubString(long pos, int length) | Exceptions are raised if pos < 1, if pos is larger than the length of the Clob, or if length <= 0.
long | length() | '
long | position(Clob searchstr, long start) | Exceptions are raised if searchStr == null or start < 1, if searchStr has length 0, or if an exception is thrown when trying to read the first char of searchStr.
long | position(String searchstr, long start) | Exceptions are raised if searchStr == null or start < 1, or if the pattern is an empty string.

Notes on mapping of java.sql.Blob and java.sql.Clob interfaces
The usual Derby locking mechanisms (shared locks) prevent other transactions from updating or deleting the database item to which the java.sql.Blob or java.sql.Clob object is a pointer. However, in some cases, Derby's instantaneous lock mechanisms could allow a period of time in which the column underlying the java.sql.Blob or java.sql.Clob is unprotected. A subsequent call to getBlob/getClob, or to a java.sql.Blob/java.sql.Clobmethod, could cause undefined behavior.
Furthermore, there is nothing to prevent the transaction that holds the java.sql.Blob/java.sql.Clob (as opposed to another transaction) from updating the underlying row. (The same problem exists with the getXXXStream methods.) Program applications to prevent updates to the underlying object while a java.sql.Blob/java.sql.Clob is open on it; failing to do this could result in undefined behavior.
Do not call more than one of the ResultSet getXXX methods on the same column if one of the methods is one of the following:

• |  | getBlob
• |  | getClob
• |  | getAsciiStream
• |  | getBinaryStream
• |  | getUnicodeStream

These methods share the same underlying stream; calling more than one of these methods on the same column could result in undefined behavior. For example:

    ResultSet rs = s.executeQuery("SELECT text FROM CLOBS WHERE i = 1");
    while (rs.next()) {
        aclob=rs.getClob(1);
        ip = rs.getAsciiStream(1);
    }

The streams that handle long-columns are not thread safe. This means that if a user chooses to open multiple threads and access the stream from each thread, the resulting behavior is undefined.
Clobs are not locale-sensitive.
JDBC 2.0 features
This section documents the methods available since JDBC 2.0 that are supported by Derby.
java.sql.CallableStatement interface: supported JDBC 2.0 methods
Table 94. JDBC 2.0 java.sql.CallableStatements Methods Supported

Returns | Signature | Implementation Notes
BigDecimal | getBigDecimal | '
Date | getDate(int, Calendar) | '
Time | getTime(int,Calendar) | '
Timestamp | getTimestamp(int, Calendar) | '

java.sql.Connection interface: supported JDBC 2.0 methods
Table 95. JDBC 2.0 Connection Methods Supported

Returns | Signature
Statement | createStatement( int resultSetType, int resultSetConcurrency)
PreparedStatement | prepareStatement(String sql, int resultSetType, int resultSetConcurrency)
CallableStatement | prepareCall(String sql, int resultSetType, int resultSetConcurrency

Implementation notes
ResultSet.TYPE_FORWARD_ONLY and ResultSet.TYPE_SCROLL_INSENSITIVE are the only result set types supported. If you request TYPE_SCROLL_SENSITIVE, Derby issues an SQLWarning and returns a TYPE_SCROLL_INSENSITIVE ResultSet.
These methods support both ResultSet.CONCUR_READ_ONLY and ResultSet.CONCUR_UPDATABLE concurrencies.
java.sql.DatabaseMetaData interface: supported JDBC 2.0 methods
Derby implements all of the JDBC 2.0 methods for this interface.
java.sql.PreparedStatement interface: supported JDBC 2.0 methods
Table 96. JDBC 2.0 java.sql.PreparedStatement Methods Supported

Returns | Signature | Implementation Notes
void | addBatch() | '
ResultSetMetaData | getMetaData() | '
void | setBlob(int i, Blob x) | '
void | setClob(int i, Clob x) | '

java.sql.ResultSet interface: supported JDBC 2.0 methods
Table 97. JDBC 2.0 ResultSet Methods Supported

Returns | Signature | Implementation Notes
boolean | absolute(int row) | '
void | afterLast() | '
void | beforeFirst() | '
void | beforeFirst() | '
void | deleteRow() | After the row is deleted, the ResultSet object will be positioned before the next row. Before issuing any methods other than close on the ResultSet object, the program will need to reposition the ResultSet object.
boolean | first() | '
Blob | getBlob(int columnIndex) | See Mapping of java.sql.Blob and java.sql.Clob interfaces
Blob | getBlob(String column-Name)
Clob | getClob(int columnIndex)
Clob | getClob(String column-Name)
int | getConcurrency() | If the Statement object has CONCUR_READ_ONLY concurrency, then this method will return ResultSet.CONCUR_READ_ONLY. But if the Statement object has CONCUR_UPDATABLE concurrency, then the return value will depend on whether the underlying language ResultSet is updatable or not. If the language ResultSet is updatable, then getConcurrency() will return ResultSet.CONCUR_UPDATABLE. If the language ResultSet is not updatable, then getConcurrency() will return ResultSet.CONCUR_READ_ONLY.
int | getFetchDirection() | '
int | getFetchSize() | Always returns 1.
int | getRow() | '
void | insertRow() | '
boolean | isAfterLast() | '
boolean | isBeforeFirst | '
boolean | isFirst() | '
boolean | isLast() | '
boolean | last() | '
void | moveToCurrentRow() | '
void | moveToInsertRow() | '
boolean | previous() | '
boolean | rowDeleted() | For forward-only result sets this methods always returns false, for scrollable result sets it returns true if the row has been deleted.
boolean | rowInserted() | Always returns false
boolean | rowUpdated() | For forward-only result sets this methods always returns false, for scrollable result sets it returns true if the row has been updated.
boolean | relative(int rows) | '
void | setFetchDirection(int direction) | '
void | setFetchSize(int rows) | A fetch size of 1 is the only size supported.
void | updateRow() | After the row is updated, the ResultSet object will be positioned before the next row. Before issuing any methods other than close on the ResultSet object, the program will need to reposition the ResultSet object.

java.sql.ResultSetMetaData interface: supported JDBC 2.0 methods
Derby implements all of the JDBC 2.0 methods for this interface.
java.sql.Statement interface: supported JDBC 2.0 methods
Table 98. JDBC2.0 java.sql.Statement Methods Supported

Returns | Signature | Implementation Notes
void | addBatch(String sql) | '
void | clearBatch() | '
int[] | executeBatch() | '
int | getFetchDirection() | Method call does not throw an exception, but call is ignored.
int | getFetchSize() | Method call does not throw an exception, but call is ignored.
int | getMaxFieldSize() | '
void | getMaxRows() | '
void | setEscapeProcessing(boolean enable) | '
void | setFetchDirection(int direction) | Method call does not throw an exception, but call is ignored.
void | setFetchSize(int rows) | Method call does not throw an exception, but call is ignored.
void | setMaxFieldSize(int max) | Has no effect on Blobs and Clobs.
void | setMaxRows() | '

java.sql.BatchUpdateException class
Thrown if there is a problem with a batch update.
JDBC Package for Connected Device Configuration/Foundation Profile (JSR169)
Derby supports the JDBC API defined for the Connected Device Configuration/Foundation Profile, also known as JSR169. The features supported are a subset of the JDBC 3.0 specification. Support for JSR169 is limited to the embedded driver. Derby does not support using the Network Server under JSR169.
To obtain a connection under JSR169 specifications, use the org.apache.derby.jdbc.EmbeddedSimpleDataSource class. This class is identical in implementation to the org.apache.derby.jdbc.EmbeddedDataSource class. See the Java DB Developer's Guide for information on using the properties of the org.apache.derby.jdbc.EmbeddedDataSource class.
Some other features to note concerning the JSR169 implementation using Derby:

• |  | Applications must get and set DECIMAL values using alternate JDBC getXXX and setXXX methods, such as getString() and setString(). Any alternate method that works against a DECIMAL type with JDBC 2.0 or 3.0 will work in JSR169.
• |  | Java functions and procedures that use server-side JDBC parameters such as CONTAINS SQL, READS SQL DATA or MODIFIES SQL DATA are not supported in JSR169.
• |  | The standard API used to obtain a connection (jdbc:default:connection) is not supported in JSR169. A runtime error may occur when the routine tries to obtain a connection using jdbc:default:connection.
• |  | Diagnostic tables are not supported.
• |  | Triggers are not supported.
• |  | Encrypted databases are not supported.
• |  | DriverManager is not supported. You cannot use DriverManager.getConnection() to obtain a connection.

JDBC 3.0 features
JDBC 3.0 adds some functionality to the core API. This section documents the features supported by Derby.
Note: These features are present only in a Java 2 version 1.4 or higher environment.
These features are:

• |  | New DatabaseMetaData methods. See java.sql.DatabaseMetaData interface: supported JDBC 3.0 methods.
• |  | Retrieval of parameter metadata. See java.sql.ParameterMetaData interface: supported JDBC 3.0 methods and java.sql.PreparedStatement interface: supported JDBC 3.0 methods.
• |  | Retrieval of auto-generated keys. See java.sql.Statement interface: supported JDBC 3.0 methods and java.sql.DatabaseMetaData interface: supported JDBC 3.0 methods.
• |  | Savepoints. See java.sql.Savepoint interface and java.sql.Connection interface: supported JDBC 3.0 methods.
• |  | HOLD Cursors. See java.sql.DatabaseMetaData interface: supported JDBC 3.0 methods.

java.sql.Connection interface: supported JDBC 3.0 methods
Table 99. JDBC 3.0 Connection Methods Supported

Returns | Signature | Implementation Notes
Savepoint | setSavepoint (String name) | Creates a savepoint with the given name in the current transaction and returns the new Savepoint object that represents it.
Savepoint | setSavepoint () | Creates an unnamed savepoint in the current transaction and returns the new Savepoint object that represents it.
void | releaseSavepoint (Savepoint savepoint) | Removes the given Savepoint object from the current transaction.
void | rollback(Savepoint savepoint) | Undoes all changes made after the given Savepoint object was set.
PreparedStatement | prepareStatement(String sql, int autoGeneratedKeys) | autoGeneratedKeys argument is ignored unless sql is an INSERT statement.
PreparedStatement | prepareStatement(String sql, int [] columnIndexes) | Column indexes are ignored unless sql is an INSERT statement. Every column index in the array must correlate to an auto-increment column within the target table of the INSERT. Supported in embedded mode only.
PreparedStatement | prepareStatement(String sql, String [] columnNames) | Column names are ignored unless sql is an INSERT statement. Every column name in the array must designate an auto-increment column within the target table of the INSERT. Supported in embedded mode only.

• |  | Autogenerated keys

java.sql.DatabaseMetaData interface: supported JDBC 3.0 methods
Table 100. JDBC 3.0 DatabaseMetaData Methods Supported

Returns | Signature | Implementation Notes
boolean | supportsSavepoints() | '
int | getDatabaseMajorVersion() | '
int | getDatabaseMinorVersion() | '
int | getJDBCMajorVersion() | '
int | getJDBCMinorVersion() | '
int | getSQLStateType() | '
boolean | supportsNamedParameters() | '
boolean | supportsMultipleOpenResults() | '
boolean | supportsGetGeneratedKeys() | '
boolean | supportsResultSetHoldability(int holdability) | '
int | getResultSetHoldability() | returns ResultSet.HOLD_CURSORS_OVER_COMMIT

java.sql.ParameterMetaData interface: supported JDBC 3.0 methods
ParameterMetaData is new in JDBC 3.0. It describes the number, type, and properties of parameters to prepared statements. The method PreparedStatement.getParameterMetaData returns a ParameterMetaData object that describes the parameter markers that appear in the PreparedStatement object. See java.sql.PreparedStatement interface: supported JDBC 3.0 methods for more information.
Interface ParameterMetaData methods are listed below.
Table 101. JDBC 3.0 ParameterMetaData Methods

Returns | Signature | Implementation Notes
int | getParameterCount() | '
int | isNullable(int param) | '
boolean | isSigned(int param) | '
int | getPrecision(int param) | '
int | getScale(int param) | '
int | getParameterType(int param) | '
String | getParamterTypeName (int param) | '
String | getParamterClassName (int param) | '
int | getParameterMode (int param) | '

java.sql.PreparedStatement interface: supported JDBC 3.0 methods
The method PreparedStatement.getParameterMetaData returns a ParameterMetaData object describing the parameter markers that appear in the PreparedStatement object. See java.sql.ParameterMetaData interface: supported JDBC 3.0 methods for more information.
Table 102. JDBC 3.0 PreparedStatement Methods

Returns | Signature | Implementation Notes
ParameterMetaData | getParameterMetaData() | '

java.sql.Savepoint interface
The Savepoint interface is new in JDBC 3.0. It contains new methods to set, release, or roll back a transaction to designated savepoints. Once a savepoint has been set, the transaction can be rolled back to that savepoint without affecting preceding work. Savepoints provide finer-grained control of transactions by marking intermediate points within a transaction.
Setting and rolling back to a savepoint
The JDBC 3.0 API adds the method Connection.setSavepoint, which sets a savepoint within the current transaction. The Connection.rollback method has been overloaded to take a savepoint argument. See java.sql.Connection interface: supported JDBC 3.0 methods for more information.
The code example below inserts a row into a table, sets the savepoint svpt1, and then inserts a second row. When the transaction is later rolled back to svpt1, the second insertion is undone, but the first insertion remains intact. In other words, when the transaction is committed, only the row containing '1' will be added to TABLE1.

    conn.setAutoCommit(false); // Autocommit must be off to use savepoints.
    Statement stmt = conn.createStatement();
    int rows = stmt.executeUpdate("INSERT INTO TABLE1 (COL1) VALUES(1)");
    // set savepoint
    Savepoint svpt1 = conn.setSavepoint("S1");
    rows = stmt.executeUpdate("INSERT INTO TABLE1 (COL1) VALUES (2)");
    ...
    conn.rollback(svpt1);
    ...
    conn.commit();

Releasing a savepoint
The method Connection.releaseSavepoint takes a Savepoint object as a parameter and removes it from the current transaction. Once a savepoint has been released, attempting to reference it in a rollback operation will cause an SQLException to be thrown.
Any savepoints that have been created in a transaction are automatically released and become invalid when the transaction is committed or when the entire transaction is rolled back.
Rolling a transaction back to a savepoint automatically releases and makes invalid any other savepoints created after the savepoint in question.
Rules for savepoints
The savepoint cannot be set within a batch of statements to enabled partial recovery. If a savepoint is set any time before the method executeBatch is called, it is set before any of the statements that have been added to the batch are executed.
A savepoint-Name can be reused after it has been released explicitly (by issuing a release of savepoint) or implicitly (by issuing a connection commit/rollback).
Restrictions on savepoints
Derby does not support savepoints within a trigger.
Derby does not release locks as part of the rollback to savepoint.
Table 103. JDBC 3.0 Savepoint Methods

Returns | Signature | Implementation Notes
int | getSavepointId() | Throws SQLException if this is a named savepoint. Retrieves the generated ID for the savepoint that this Savepoint object represents.
String | getSavepointName() | Throws SQLException if this is an unnamed savepoint. Retrieves the name of the savepoint that this Savepoint object represents.

java.sql.Statement interface: supported JDBC 3.0 methods
Table 104. JDBC 3.0 Statement Methods

Returns | Signature | Implementation Notes
ResultSet | getGeneratedKeys() | If the user has indicated that auto-generated keys should be made available, this method returns the same results as a call to the IDENTITY_VAL_LOCAL function. Otherwise this method returns null.
boolean | execute(String sql, int autoGeneratedKeys) | autoGeneratedKeys argument is ignored unless sql is an INSERT statement.
boolean | execute(String sql, int [] columnIndexes) | Column indexes are ignored unless sql is an INSERT statement. Every column index in the array must correlate to an auto-increment column within the target table of the INSERT. Supported in embedded mode only.
boolean | execute(String sql, String [] columnNames) | Column names are ignored unless sql is an INSERT statement. Every column name in the array must designate an auto-increment column within the target table of the INSERT. Supported in embedded mode only.
int | executeUpdate(String sql, int autoGeneratedKeys) | autoGeneratedKeys argument is ignored unless sql is an INSERT statement.
int | executeUpdate(String sql, int [] columnIndexes) | Column indexes are ignored unless sql is an INSERT statement. Every column index in the array must correlate to an auto-increment column within the target table of the INSERT. Supported in embedded mode only.
int | executeUpdate(String sql, String [] columnNames) | Column names are ignored unless sql is an INSERT statement. Every column name in the array must designate an auto-increment column within the target table of the INSERT. Supported in embedded mode only.

Autogenerated keys
JDBC 3.0's auto-generated keys feature provides a way to retrieve values from columns that are part of an index or have a default value assigned. Derby supports the auto-increment feature, which allows users to create columns in tables for which the database system automatically assigns increasing integer values. In JDBC 3.0, the method Statement.getGeneratedKeys can be called to retrieve the value of such a column. This method returns a ResultSet object with a column for the automatically generated key. Calling ResultSet.getMetaData on the ResultSet object returned by getGeneratedKeys produces a ResultSetMetaData object that is similar to that returned by IDENTITY_VAL_LOCAL.
Users can indicate that auto-generated columns should be made available for retrieval by passing one of the following values as a second argument to the Connection.prepareStatement, Statement.execute, or Statement.executeUpdate methods:

• |  | A constant indicating that auto-generated keys should be made available. The specific constant to use is Statement.RETURN_GENERATED_KEYS.
• |  | An array of the names of the columns in the inserted row that should be made available. If any column name in the array does not designate an auto-increment column, Derby will throw an error. (This argument is supported only with the Derby embedded driver.)
• |  | An array of the positions of the columns in the inserted row that should be made available. If any column position in the array does not correlate to an auto-increment column, Derby will throw an error. (This argument is supported only with the Derby embedded driver.)

Example
Assume that we have a table TABLE1 defined as follows:

    CREATE TABLE TABLE1 (C11 int, C12 int GENERATED ALWAYS AS IDENTITY)

The following three code fragments will all do the same thing: that is, they will create a ResultSet that contains the value of C12 that is inserted into TABLE1.
Code fragment 1:

    Statement stmt = conn.createStatement();
    stmt.execute(
        "INSERT INTO TABLE1 (C11) VALUES (1)",
        Statement.RETURN_GENERATED_KEYS);
    ResultSet rs = stmt.getGeneratedKeys();

Code fragment 2:

    Statement stmt = conn.createStatement();
    String [] colNames = new String [] { "C12" };
    stmt.execute(
        "INSERT INTO TABLE1 (C11) VALUES (1)",
        colNames);
    ResultSet rs = stmt.getGeneratedKeys();

Code fragment 3:

    Statement stmt = conn.createStatement();
    int [] colIndexes = new int [] { 2 };
    stmt.execute(
        "INSERT INTO TABLE1 (C11) VALUES (1)",
        colIndexes);
    ResultSet rs = stmt.getGeneratedKeys();

If there is no indication that auto-generated columns should be made available for retrieval, a call to Statement.getGeneratedKeys will return a null ResultSet.
JDBC 4.0-only features
JDBC 4.0 adds some functionality to the core API. This section documents the features supported by Derby.
Note: These features are present only in a JDK 1.6 or higher environment.
These features are:

• |  | DataSources. To support the JDBC 4.0 ease of development, Derby introduces new implementations of javax.sql.DataSource. See javax.sql.DataSource interface: JDBC 4.0 features.
• |  | Autoloading of JDBC drivers. In earlier versions of JDBC, applications had to manually register drivers before requesting Connections. With JDBC 4.0, applications no longer need to issue a Class.forName() on the driver name; instead, the DriverManager will find an appropriate JDBC driver when the application requests a Connection.
• |  | SQLExceptions. JDBC 4.0 introduces refined subclasses of SQLException. See Refined subclasses of SQLException.
• |  | Wrappers. JDBC 4.0 introduces the concept of wrapped JDBC objects. This is a formal mechanism by which application servers can look for vendor-specific extensions inside standard JDBC objects like Connections, Statements, and ResultSets. For Derby, this is a vacuous exercise because Derby does not expose any of these extensions.
• |  | Statement events. With JDBC 4.0, Connection pools can listen for Statement closing and Statement error events. New methods were added to javax.sql.PooledConnection: addStatementEventListener and removeStatementEventListener.
• |  | Streaming APIs. JDBC 4.0 adds new overloads of the streaming methods in CallableStatement, PreparedStatement, and ResultSet. These are the setXXX and updateXXX methods which take java.io.InputStream and java.io.Reader arguments. The new overloads allow you to omit the length arguments or to specify long lengths.
• |  | New methods. New methods were added to the following interfaces: javax.sql.Connection, javax.sql.DatabaseMetaData, and javax.sql.Statement. See java.sql.Connection interface: JDBC 4.0 features, java.sql.DatabaseMetaData interface: JDBC 4.0 features, java.sql.Statement interface: JDBC 4.0 features.

Refined subclasses of SQLException
If your application runs on JDK 1.6 or higher, exceptions raised by Derby will generally be one of the refined subclasses of SQLException, introduced by JDBC 4.0. These refined exceptions are raised under the conditions described by their respective javadoc.

• |  | java.sql.SQLClientInfoException
• |  | java.sql.SQLDataException
• |  | java.sql.SQLFeatureNotSupportedException
• |  | java.sql.SQLIntegrityConstraintViolationException
• |  | java.sql.SQLInvalidAuthorizationSpecException
• |  | java.sql.SQLSyntaxErrorException
• |  | java.sql.SQLTransactionRollbackException
• |  | java.sql.SQLTransientConnectionException

java.sql.Connection interface: JDBC 4.0 features
JDBC 4.0 adds new capabilities to Connections:

• |  | LOB creation - New methods, createBlob() and createClob() let you create empty Blobs and Clobs, which you can then fill up before stuffing into a column.
• |  | Validity tracking - The isValid method tells you whether your Connection is still alive.

java.sql.DatabaseMetaData interface: JDBC 4.0 features
Derby implements all of the new metadata methods added by JDBC 4.0.

• |  | Capability reports - JDBC 4.0 adds new methods for querying the capabilities of a database. These include autoCommitFailureClosesAllResultSets, providesQueryObjectGenerator, getClientInfoProperties, and supportsStoredFunctionsUsingCallSyntax.
• |  | Column metadata - The getColumns method reports IS_AUTOINCREMENT = YES if a column is generated.
• |  | Function metadata - JDBC 4.0 adds new methods for inspecting the arguments and return types of functions, including user-defined functions. These new methods are getFunctions and getFunctionColumns. These methods behave similarly to getProcedures and getProcedureColumns.
• |  | Procedure metadata - The getProcedureColumns method reports additional information about procedure arguments. For more information, see the javadoc for this method. The new columns in the ResultSet returned by getProcedureColumns are: COLUMN_DEF, SQL_DATA_TYPE, SQL_DATETIME_SUB, CHAR_OCTET_LENGTH, ORDINAL_POSITION, IS_NULLABLE, and SPECIFIC_NAME.
• |  | Schema metadata - JDBC 4.0 adds a new getSchemas overload, which lets you look up schemas based on a name pattern.

java.sql.Statement interface: JDBC 4.0 features
Derby's Statements implement the following new metadata methods added by JDBC 4.0.

• |  | Pooling support - JDBC 4.0 adds new methods to help application servers manage pooled Statements: isPoolable and setPoolable.
• |  | Validity tracking - JDBC 4.0 lets you track the validity of a Statement through the new isClosed method.

javax.sql.DataSource interface: JDBC 4.0 features
Derby has added new JDBC 4.0-specific DataSources. Use these DataSources if your application runs on JDK 1.6 or higher.

• |  | org.apache.derby.jdbc.EmbeddedConnectionPoolDataSource40
• |  | org.apache.derby.jdbc.EmbeddedDataSource40
• |  | org.apache.derby.jdbc.EmbeddedXADataSource40
• |  | org.apache.derby.jdbc.ClientConnectionPoolDataSource40
• |  | org.apache.derby.jdbc.ClientDataSource40
• |  | org.apache.derby.jdbc.ClientXADataSource40

JDBC escape syntax
JDBC provides a way of smoothing out some of the differences in the way different DBMS vendors implement SQL. This is called escape syntax. Escape syntax signals that the JDBC driver, which is provided by a particular vendor, scans for any escape syntax and converts it into the code that the particular database understands. This makes escape syntax DBMS-independent.
A JDBC escape clause begins and ends with curly braces. A keyword always follows the opening curly brace:

    {keyword }

Derby supports the following JDBC escape keywords, which are case-insensitive:

• |  | JDBC escape keyword for call statements The escape keyword for use in CallableStatements.
• |  | JDBC escape syntax The escape keyword for date formats.
• |  | JDBC escape syntax for LIKE clauses The keyword for specifying escape characters for LIKE clauses.
• |  | JDBC escape syntax for fn keyword The escape keyword for scalar functions.
• |  | JDBC escape syntax for outer joins The escape keyword for outer joins.
• |  | JDBC escape syntax for time formats The escape keyword for time formats.
• |  | JDBC escape syntax for timestamp formats The escape keyword for timestamp formats.

Other JDBC escape keywords are not supported.
Note: Derby returns the SQL unchanged in the Connection.nativeSQL call, since the escape syntax is native to SQL. In addition, it is unnecessary to call Statement.setEscapeProcessing for this reason.
JDBC escape keyword for call statements
This syntax is supported for a java.sql.Statement and a java.sql.PreparedStatement in addition to a CallableStatement.
Syntax

    {call statement }

    -- Call a Java procedure
    { call TOURS.BOOK_TOUR(?, ?) }

JDBC escape syntax
Derby interprets the JDBC escape syntax for date as equivalent to the SQL syntax for dates.
Syntax

    {d 'yyyy-mm-dd'}

Equivalent to

    DATE('yyyy-mm-dd')

    VALUES {d '1999-01-09'}

JDBC escape syntax for LIKE clauses
The percent sign % and underscore _ are metacharacters within SQL LIKE clauses. JDBC provides syntax to force these characters to be interpreted literally. The JDBC clause immediately following a LIKE expression allows you to specify an escape character:
Syntax

    WHERE CharacterExpression [ NOT ] LIKE
        CharacterExpressionWithWildCard
        { ESCAPE 'escapeCharacter' }

    -- find all rows in which a begins with the character "%"
    SELECT a FROM tabA WHERE a LIKE '$%%' {escape '$'}
    -- find all rows in which a ends with the character "_"
    SELECT a FROM tabA WHERE a LIKE '%=_' {escape '='}

Note: ? is not permitted as an escape character if the LIKE pattern is also a dynamic parameter (?).
In some languages, a single character consists of more than one collation unit (a 16-bit character). The escapeCharacter used in the escape clause must be a single collation unit in order to work properly.
You can also use the escape character sequence for LIKE without using JDBC's curly braces; see Boolean expressions.
JDBC escape syntax for fn keyword
You can specify functions in JDBC escape syntax, by using the fn keyword.
Syntax

    {fn functionCall}

where functionCall is the name of one of the following scalar functions:
abs
Returns the absolute value of a number.

    abs(NumericExpression)

The JDBC escape syntax {fn abs(NumericExpression)} is equivalent to the built-in syntax ABSOLUTE(NumericExpression). For more information, see ABS or ABSVAL function.
acos
Returns the arc cosine of a specified number.

    acos(number)

The JDBC escape syntax {fn acos(number)} is equivalent to the built-in syntax ACOS(number). For more information, see ACOS function.
asin
Returns the arc sine of a specified number.

    asin(number)

The JDBC escape syntax {fn asin(number)} is equivalent to the built-in syntax ASIN(number). For more information, see ASIN function.
atan
Returns the arc tangent of a specified number.

    atan(number)

The JDBC escape syntax {fn atan(number)} is equivalent to the built-in syntax ATAN(number). For more information, see ATAN function.
ceiling
Rounds the specified number up, and returns the smallest number that is greater than or equal to the specified number.

    ceiling(number)

The JDBC escape syntax {fn ceiling(number)} is equivalent to the built-in syntax CEILING(number). For more information, see CEIL or CEILING function.
concat
Returns the concatenation of character strings.

    concat(CharacterExpression, CharacterExpression)

Character string formed by appending the second string to the first string. If either string is null, the result is NULL. The JDBC escape syntax {fn concat (CharacterExpression, CharacterExpression) is equivalent to the built-in syntax { CharacterExpression || CharacterExpression }. For more information, see Concatenation operator.
cos
Returns the cosine of a specified number.

    cos(number)

The JDBC escape syntax {fn cos(number)} is equivalent to the built-in syntax COS(number). For more information, see COS function.
degrees
Converts a specified number from radians to degrees.

    degrees(number)

The JDBC escape syntax {fn degrees(number)} is equivalent to the built-in syntax DEGREES(number). For more information, see DEGREES function.
exp
Returns e raised to the power of the specified number.

    exp(number)

The JDBC escape syntax {fn exp(number)} is equivalent to the built-in syntax EXP(number). For more information, see EXP function.
floor
Rounds the specified number down, and returns the largest number that is less than or equal to the specified number.

    floor(number)

The JDBC escape syntax {fn floor(number)} is equivalent to the built-in syntax FLOOR(number). For more information, see FLOOR function.
locate
Returns the position in the second CharacterExpression of the first occurrence of the first CharacterExpression. Searches from the beginning of the second CharacterExpression, unless the startIndex parameter is specified.

    locate(CharacterExpression,CharacterExpression [, startIndex] )

The JDBC escape syntax {fn locate(CharacterExpression,CharacterExpression [, startIndex] )} is equivalent to the built-in syntax LOCATE(CharacterExpression, CharacterExpression [, StartPosition] ). For more information, see LOCATE function.
log
Returns the natural logarithm (base e) of the specified number.

    log(number)

The JDBC escape syntax {fn log(number)} is equivalent to the built-in syntax LOG(number). For more information, see LN or LOG function.
log10
Returns the base-10 logarithm of the specified number.

    log10(number)

The JDBC escape syntax {fn log10(number)} is equivalent to the built-in syntax LOG10(number). For more information, see LOG10 function.
mod
Returns the remainder (modulus) of argument 1 divided by argument 2. The result is negative only if argument 1 is negative.

    mod(integer_type, integer_type)

For more information, see MOD function.
pi
Returns a value that is closer than any other value to pi.

    pi()

The JDBC escape syntax {fn pi()} is equivalent to the built-in syntax PI(). For more information, see PI function.
radians
Converts a specified number from degrees to radians.

    radians(number)

The JDBC escape syntax {fn radians(number)} is equivalent to the built-in syntax RADIANS(number). For more information, see RADIANS function.
sin
Returns the sine of a specified number.

    sin(number)

The JDBC escape syntax {fn sin(number)} is equivalent to the built-in syntax SIN(number). For more information, see SIN function.
sqrt
Returns the square root of floating point number.

    sqrt(FloatingPointExpression)

The JDBC escape syntax {fn sqrt (FloatingPointExpression)} is equivalent to the built-in syntax SQRT(FloatingPointExpression). For more information, see SQRT function.
substring
Forms a character string by extracting length characters from the CharacterExpression beginning at startIndex. The index of the first character in the CharacterExpression is 1.

    substring(CharacterExpression, startIndex, length)

tan
Returns the tangent of a specified number.

    tan(number)

The JDBC escape syntax {fn tan(number)} is equivalent to the built-in syntax TAN(number). For more information, see TAN function.
TIMESTAMPADD
Use the TIMESTAMPADD function to add the value of an interval to a timestamp. The function applies the integer to the specified timestamp based on the interval type and returns the sum as a new timestamp. You can subtract from the timestamp by using negative integers.
The TIMESTAMPADD is a JDBC escaped function, and is only accessible by using the JDBC escape function syntax.

    TIMESTAMPADD( interval, integerExpression, timestampExpression )

To perform TIMESTAMPADD on dates and times, it is necessary to convert the dates and times to timestamps. Dates are converted to timestamps by putting 00:00:00.0 in the time-of-day fields. Times are converted to timestamps by putting the current date in the date fields.
You should not put a datetime column inside of a timestamp arithmetic function in WHERE clauses because the optimizer will not use any index on the column.
TIMESTAMPDIFF
Use the TIMESTAMPDIFF function to find the difference between two timestamp values at a specified interval. For example, the function can return the number of minutes between two specified timestamps.
The TIMESTAMPDIFF is a JDBC escaped function, and is only accessible by using the JDBC escape function syntax.

    TIMESTAMPDIFF( interval, timestampExpression1, timestampExpression2 )

To perform TIMESTAMPDIFF on dates and times, it is necessary to convert the dates and times to timestamps. Dates are converted to timestamps by putting 00:00:00.0 in the time-of-day fields. Times are converted to timestamps by putting the current date in the date fields.
You should not put a datetime column inside of a timestamp arithmetic function in WHERE clauses because the optimizer will not use any index on the column.
Valid intervals for TIMESTAMPADD and TIMESTAMPDIFF
The TIMESTAMPADD and TIMESTAMPDIFF functions are used to perform arithmetic with timestamps. These two functions use the following valid intervals for arithmetic operations:

• |  | SQL_TSI_DAY
• |  | SQL_TSI_FRAC_SECOND
• |  | SQL_TSI_HOUR
• |  | SQL_TSI_MINUTE
• |  | SQL_TSI_MONTH
• |  | SQL_TSI_QUARTER
• |  | SQL_TSI_SECOND
• |  | SQL_TSI_WEEK
• |  | SQL_TSI_YEAR

Examples for the TIMESTAMPADD and TIMESTAMPDIFF escape functions
To return a timestamp value one month later than the current timestamp, use the following syntax:

    {fn TIMESTAMPADD( SQL_TSI_MONTH, 1, CURRENT_TIMESTAMP)}

To return the number of weeks between now and the specified time on January 1, 2008, use the following syntax:

    {fn TIMESTAMPDIFF(SQL_TSI_WEEK, CURRENT_TIMESTAMP,
      timestamp('2008-01-01-12.00.00.000000'))}

JDBC escape syntax for outer joins
Derby interprets the JDBC escape syntax for outer joins (and all join operations) as equivalent to the correct SQL syntax for outer joins or the appropriate join operation.
For information about join operations, see JOIN operations.
Syntax

    {oj JOIN operations [JOIN operations ]* }

Equivalent to

    JOIN operations [JOIN operations ]*

    -- outer join
    SELECT *
    FROM
    {oj Countries LEFT OUTER JOIN Cities ON
       (Countries.country_ISO_code=Cities.country_ISO_code)}
    -- another join operation
    SELECT *
    FROM
    {oj Countries JOIN Cities ON (Countries.country_ISO_code=Cities.country_ISO_code)}
    -- a TableExpression can be a joinOperation. Therefore
    -- you can have multiple join operations in a FROM clause
    SELECT E.EMPNO, E.LASTNAME, M.EMPNO, M.LASTNAME
    FROM {oj EMPLOYEE E INNER JOIN DEPARTMENT
    INNER JOIN EMPLOYEE M ON MGRNO = M.EMPNO ON E.WORKDEPT = DEPTNO};

JDBC escape syntax for time formats
Derby interprets the JDBC escape syntax for time as equivalent to the correct SQL syntax for times. Derby also supports the ISO format of 8 characters (6 digits, and 2 decimal points).
Syntax

    {t 'hh:mm:ss'}

Equivalent to

    TIME 'hh:mm:ss'

Example

    VALUES {t '20:00:03'}

JDBC escape syntax for date formats
Derby interprets the JDBC escape syntax for dates as equivalent to the correct SQL syntax for dates.
Syntax

    {d 'yyyy-mm-dd'}

Equivalent to

    DATE 'yyyy-mm-dd'

Example

    VALUES {d '1995-12-19'}

JDBC escape syntax for timestamp formats
Derby interprets the JDBC escape syntax for timestamp as equivalent to the correct SQL syntax for timestamps. Derby also supports the ISO format of 23 characters (17 digits, 3 dashes, and 3 decimal points).
Syntax

    {ts 'yyyy-mm-dd hh:mm:ss.f...'}

Equivalent to

    TIMESTAMP 'yyyy-mm-dd hh:mm:ss.f...'

The fractional portion of timestamp constants (.f...) can be omitted.

    VALUES {ts '1999-01-09 20:11:11.123455'}

Setting attributes for the database connection URL
Derby allows you to supply a list of attributes to its database connection URL, which is a JDBC feature.
The attributes are specific to Derby.
You typically set attributes in a semicolon-separated list following the protocol and subprotocol. For information on how you set attributes, see Attributes of the Derby database connection URL. This chapter provides reference information only.
Note: Attributes are not parsed for correctness. If you pass in an incorrect attribute or corresponding value, it is simply ignored.
bootPassword=key attribute
Function
Specifies the key to use to :

• |  | Encrypt a new database
• |  | Configure an existing unencrypted database for encryption
• |  | Boot an existing encrypted database

Specify an alphanumeric string that is at least eight characters long.
Combining with other attributes
When you create a new database, the bootPassword=key attribute must be combined with the create=true and dataEncryption=true attributes.
When you configure an existing unencrypted database for encryption, the bootPassword=key attribute must be combined with the dataEncryption=true attribute. For an existing, unencrypted database for which authentication and SQL authorization are both enabled, only the database owner can perform encryption. Please see "Enabling user authentication" and "Setting the SQL standard authorization mode" in the Java DB Developer's Guide for more information.
When you boot an existing encrypted database, no other attributes are necessary.
Examples

    -- create a new, encrypted database
    jdbc:derby:newDB;create=true;dataEncryption=true;
        bootPassword=cseveryPlace
    -- configure an existing unencrypted database for encryption
    jdbc:derby:salesdb;dataEncryption=true;bootPassword=cseveryPlace
    -- boot an existing encrypted database
    jdbc:derby:encryptedDB;bootPassword=cseveryPlace

collation=collation attribute
Function
The collation attribute is an optional attribute that specifies whether collation is based on the territory specified for the database or Unicode codepoint collation. The valid values for the collation attribute are: TERRITORY_BASED and UCS_BASIC. The default collation is Unicode codepoint collation (UCS_BASIC).
Restriction: The collation attribute can be specified only when you create a database. You cannot specify this attribute on an existing database or when you upgrade a database.
If you include the collation attribute with the value TERRITORY_BASED when you create the Derby database, the collation is based on the language and country codes that you specify with the territory attribute.
If you do not specify the territory attribute when you create the database, Derby uses the java.util.Locale.getDefault method to determine the current value of the default locale for this instance of the Java Virtual Machine (JVM).
Note: The collation attribute applies only to user-defined tables. The system tables use the Unicode codepoint collation.
Example
The following example shows the URL to create the MexicanDB database. The territory attribute specifies Spanish for the language code and Mexico for the country code. The collation attribute specifies that the collation for the database is territory based.

    jdbc:derby:MexicanDB;create=true;territory=es_MX;collation=TERRITORY_BASED

For information on how Derby handles collation, see "Character-based collation in Derby" in the Java DB Developer's Guide
create=true attribute
Function
Creates the standard database specified within the database connection URL Derby system and then connects to it. If the database cannot be created, the error appears in the error log and the connection attempt fails with an SQLException indicating that the database cannot be found.
If the database already exists, creates a connection to the existing database and an SQLWarning is issued.
JDBC does not remove the database on failure to connect at create time if failure occurs after the database call occurs. If a database connection URL used create=true and the connection fails to be created, check for the database directory. If it exists, remove it and its contents before the next attempt to create the database.
Database owner
When the database is created, the current authorization identifier becomes the database owner (see the user=userName attribute). If authentication and SQL authorization are both enabled (see "Enabling user authentication" and "Setting the SQL standard authorization mode" in the Java DB Developer's Guide), only the database owner can shut down the database, encrypt it, reencrypt it with a new boot password or new encryption key, or perform a full upgrade. If authentication is not enabled, and no user is supplied, the database owner defaults to "APP", which is also the name of the default schema (see SET SCHEMA statement).
Combining with other attributes
You must specify a databaseName (after the subprotocol in the database connection URL) or a databaseName=nameofDatabase attribute with this attribute.
You can combine this attribute with other attributes. To specify a territory when creating a database, use the territory=ll_CC attribute.
Note: If you specify create=true and the database already exists, an SQLWarning is raised.

    jdbc:derby:sampleDB;create=true

    jdbc:derby:;databaseName=newDB;create=true;

createFrom=path attribute
Function
You can specify the createFrom=path attribute in the boot time connection URL to create a database using a full backup at a specified location. If there is a database with the same name in derby.system.home, an error will occur and the existing database will be left intact. If there is not an existing database with the same name in the current derby.system.home location, the whole database is copied from the backup location to the derby.system.home location and started.
The Log files are copied to the default location. The logDevice attribute can be used in conjunction with createFrom=path to store logs in a different location. With createFrom=path you do not need to copy the individual log files to the log directory.
Combining with other attributes
Do not combine this attribute with rollForwardRecoveryFrom, restoreFrom, or create.

    URL: jdbc:derby:wombat;createFrom=d:/backup/wombat

databaseName=nameofDatabase attribute
Function
Specifies a database name for a connection; it can be used instead of specifying the database name in after the subprotocol.
For example, these URL (and Properties object) combinations are equivalent:

• |  | jdbc:derby:toursDB
• |  | jdbc:derby:;databaseName=toursDB
• |  | jdbc:derby:(with a property databaseName and its value set to toursDB in the Properties object passed into a connection request)

If the database name is specified both in the URL (as a subname) and as an attribute, the database name set as the subname has priority. For example, the following database connection URL connects to toursDB:

    jdbc:derby:toursDB;databaseName=flightsDB

Allowing the database name to be set as an attribute allows the getPropertyInfo method to return a list of choices for the database name based on the set of databases known to Derby. For more information, see java.sql.Driver.getPropertyInfo method.
Combining with other attributes
You can combine this attribute with all other attributes.

    jdbc:derby:;databaseName=newDB;create=true

dataEncryption=true attribute
Function
Specifies data encryption on disk for a new database or to configure an existing unencrypted database for encryption. For information about data encryption, see "Encrypting databases on disk" in the Java DB Developer's Guide.
Combining with other attributes
The dataEncryption attribute must be combined with the bootPassword=key attribute or the newEncryptionKey=key attribute. You have the option of also specifying the encryptionProvider=providerName and encryptionAlgorithm=algorithm attributes.
For an existing, unencrypted database for which authentication and SQL authorization are both enabled, only the database owner can perform encryption. See also "Enabling user authentication" and "Setting the SQL standard authorization mode" in the Java DB Developer's Guide for more information.
Examples

     -- encrypt a new database
    jdbc:derby:encryptedDB;create=true;dataEncryption=true;
        bootPassword=cLo4u922sc23aPe
     -- configure an existing unencrypted database for encryption
       jdbc:derby:salesdb;dataEncryption=true;bootPassword=cLo4u922sc23aPe

encryptionKey=key attribute
Function
Specifies the external key to use to:

• |  | Encrypt a new database
• |  | Configure an existing unencrypted database for encryption
• |  | Boot an existing encrypted database

Your application must provide the encryption key.
Combining with other attributes
When creating a new database, you must combine the encryptionKey attribute with the create=true and dataEncryption=true attributes.
When you configure an existing unencrypted database for encryption, the encryptionKey attribute must be combined with the dataEncryption=true attribute. For an existing, unencrypted database for which authentication and SQL authorization are both enabled, only the database owner can perform encryption. Please see "Enabling user authentication" and "Setting the SQL standard authorization mode" in the Java DB Developer's Guide for more information.
When booting an existing encrypted database, you must also specify the encryptionAlgorithm attribute if the algorithm that was used when the database was created is not the default algorithm.
The default encryption algorithm used by Derby is DES/CBC/NoPadding.
Examples
Example of a JDBC URL that creates a new encrypted database:

    jdbc:derby:newDB;create=true;dataEncryption=true;
       encryptionAlgorithm=DES/CBC/NoPadding;encryptionKey=6162636465666768

Example of a JDBC URL that configures an existing unencrypted database for encryption:

    jdbc:derby:salesdb;dataEncryption=true;encryptionKey=6162636465666768

Example of a JDBC URL that boots an encrypted database:

    jdbc:derby:encryptedDB;encryptionKey=6162636465666768

encryptionProvider=providerName attribute
Function
Specifies the provider for data encryption. For information about data encryption, see "Encrypting databases on disk" in the Java DB Developer's Guide.
If this attribute is not specified, the default encryption provider is the one included in the JVM that you are using.
Combining with other attributes
The encryptionProvider attribute must be combined with the bootPassword=key and dataEncryption=true attributes. You can also specify the encryptionAlgorithm=algorithm attribute.
For an existing, unencrypted database for which authentication and SQL authorization are both enabled, only the database owner can perform encryption or reencryption. Please see "Enabling user authentication" and "Setting the SQL standard authorization mode" in the Java DB Developer's Guide for more information.
Examples

    -- create a new, encrypted database
    jdbc:derby:encryptedDB;create=true;dataEncryption=true;
        encryptionProvider=com.sun.crypto.provider.SunJCE;
        encryptionAlgorithm=DESede/CBC/NoPadding;
        bootPassword=cLo4u922sc23aPe
    -- configure an existing database for encryption
        jdbc:derby:salesdb;dataEncryption=true;
        encryptionProvider=com.sun.crypto.provider.SunJCE;
        encryptionAlgorithm=DESede/CBC/NoPadding;
        bootPassword=cLo4u922sc23aPe

encryptionAlgorithm=algorithm attribute
Function
Specifies the algorithm for data encryption.
Use the Java conventions when you specify the algorithm, for example:

    algorithmName/feedbackMode/padding

The only padding type that is allowed with Derby is NoPadding.
If no encryption algorithm is specified, the default value is DES/CBC/NoPadding.
For information about data encryption, see "Encrypting databases on disk" in the Java DB Developer's Guide.
Combining with other attributes
The encryptionAlgorithm attribute must be combined with the bootPassword=key attribute and the dataEncryption=true attribute. You have the option of also specifying the encryptionProvider=providerName attribute to specify the encryption provider of the algorithm.
For an existing database for which authentication and SQL authorization are both enabled, only the database owner can perform encryption or reencryption. Please see "Enabling user authentication" and "Setting the SQL standard authorization mode" in the Java DB Developer's Guide for more information.
Examples

     -- encrypt a new database
        jdbc:derby:encryptedDB;create=true;dataEncryption=true;
        encryptionProvider=com.sun.crypto.provider.SunJCE;
        encryptionAlgorithm=DESede/CBC/NoPadding;
        bootPassword=cLo4u922sc23aPe
    -- configure an existing database for encryption
        jdbc:derby:salesdb;dataEncryption=true;
        encryptionProvider=com.sun.crypto.provider.SunJCE;
        encryptionAlgorithm=DESede/CBC/NoPadding;
        bootPassword=cLo4u922sc23aPe

Note: If the specified provider does not support the specified algorithm, Derby returns an exception.
logDevice=logDirectoryPath attribute
Function
The logDirectoryPath specifies the path to the directory on which to store the database log during database creation or restore. Even if specified as a relative path, the logDirectoryPath is stored internally as an absolute path.
Combining with other attributes
Use in conjunction with create, createFrom, restoreFrom, or rollForwardRecoveryFrom.

    jdbc:derby:newDB;create=true;logDevice=d:/newDBlog

newEncryptionKey=key attribute
Function
Specifies a new external encryption key for an encrypted database. All of the existing data in the database is encrypted using the new encryption key and any new data written to the database will use this key for encryption. For more information about this attribute, see "Encrypting databases with a new external encryption key" in the Java DB Developer's Guide.
Combining with other attributes
The newEncryptionKey attribute must be combined with the encryptionKey=key attribute.
You cannot change the encryption provider or the encryption algorithm when you use the newEncryptionKey attribute.
For an existing encrypted database for which authentication and SQL authorization are both enabled, only the database owner can perform reencryption. Please see "Enabling user authentication" and "Setting the SQL standard authorization mode" in the Java DB Developer's Guide for more information.
Example

    -- specify a new encryption key for a database
    jdbc:derby:salesdb;encryptionKey=6162636465666768;newEncryptionKey=6862636465666768

newBootPassword=newPassword attribute
Function
Specifies a new boot password for an encrypted database. A new encryption key is generated internally by the engine and the key is protected using the new boot password. The newly generated encryption key encrypts the database, including the existing data. For more information about this attribute, see "Encrypting databases with a new boot password" in the Java DB Developer's Guide.
Combining with other attributes
The newBootPassword attribute must be combined with the bootPassword=key attribute.
You cannot change the encryption provider or the encryption algorithm when you use the newBootPassword attribute.
For an existing encrypted database for which authentication and SQL authorization are both enabled, only the database owner can perform reencryption. Please see "Enabling user authentication" and "Setting the SQL standard authorization mode" in the Java DB Developer's Guide for more information.
Example

    -- specify a new boot password for a database
    jdbc:derby:salesdb;bootPassword=abc1234xyz;newBootPassword=new1234xyz

password=userPassword attribute
Function
A valid password for the given user name.
Combining with other attributes
Use in conjunction with the user=userName attribute.

    jdbc:derby:toursDB;user=jack;password=upTheHill

restoreFrom=path attribute
Function
You can specify the restoreFrom=path attribute in the boot time connection URL to restore a database using a full backup from the specified location. If a database with the same name exists in the derby.system.home location, the whole database is deleted, copied from the backup location, and then restarted.
The log files are copied to the same location they were in when the backup was taken. The logDevice attribute can be used in conjunction with restoreFrom=path to store logs in a different location.
Combining with other attributes
Do not combine this attribute with createFrom, rollForwardRecoveryFrom, or create.

    URL: jdbc:derby:wombat;restoreFrom=d:/backup/wombat

rollForwardRecoveryFrom=path attribute
Function
You can specify the rollForwardRecoveryFrom=path in the boot time URL to restore the database using a backup copy and perform rollforward recovery using archived and active logs.
To restore a database using rollforward recovery, you must already have a backup copy of the database, all the archived logs since then, and the active log files. All the log files should be in the database log directory.
After a database is restored from full backup, transactions from the online archived logs and the active logs are replayed.
Combining with other attributes
Do not combine this attribute with createFrom, restoreFrom, or create.

    URL: jdbc:derby:wombat;rollForwardRecoveryFrom=d:/backup/wombat

securityMechanism=value attribute
Function
Specifies a security mechanism for client access to the Network Server. The value is numeric.
Valid numeric values are:

• |  | 8, which specifies Strong Password Substitute security. If you specify this mechanism, a strong password substitute is generated and used to authenticate the user with the network server. The original password is never sent in any form across the network.
• |  | 9, which specifies Encrypted UserID and Encrypted Password security. If you specify this mechanism, both the user ID and the password are encrypted. See "Enabling the encrypted user ID and password security mechanism" in the Java DB Server and Administration Guide for additional requirements for the use of this security mechanism.
• |  | 3, which specifies Clear Text Password security. Clear Text Password security is the default if you do not specify the securityMechanism attribute and you specify both the user=userName and password=userPassword attributes.
• |  | 4, which specifies User Only security. User Only security is the default if you do not specify the securityMechanism attribute and you specify the user=userName attribute but not the password=userPassword attribute.

Combining with other attributes
The securityMechanism attribute must be combined with the user=userName attribute.
Example

    -- specify Strong Password Substitute security
    jdbc:derby://localhost/mydb;user=myuser;password=mypassword;securityMechanism=8

shutdown=true attribute
Function
Shuts down the specified database if you specify a databaseName. (Reconnecting to the database reboots the database.) For a database for which authentication and SQL authorization are both enabled, only the database owner can perform shutdown of that database. Please see "Enabling user authentication" and "Setting the SQL standard authorization mode" in the Java DB Developer's Guide for more information.
Shuts down the entire Derby system if and only if you do not specify a databaseName.
When you are shutting down a single database, it lets Derby perform a final checkpoint on the database.
When you are shutting down a system, it lets Derby perform a final checkpoint on all system databases, deregister the JDBC driver, and shut down within the JVM before the JVM exits. A successful shutdown always results in an SQLException indicating that Derby has shut down and that there is no connection. Once Derby is shut down, you can restart it by reloading the driver. For details on restarting Derby, see "Shutting down the system" in the Java DB Developer's Guide.
Checkpointing means writing all data and transaction information to disk so that no recovery needs to be performed at the next connection.
Used to shut down the entire system only when it is embedded in an application.
Note: Any request to the DriverManager with a shutdown=true attribute raises an exception.

    -- shuts down entire system
    jdbc:derby:;shutdown=true
    -- shuts down salesDB (authentication not enabled)
    jdbc:derby:salesDB;shutdown=true

territory=ll_CC attribute
Function
When creating or upgrading a database, use this attribute to associate a non-default territory with the database. Setting the territory attribute overrides the default system territory for that database. The default system territory is found using java.util.Locale.getDefault().
Specify a territory in the form ll_CC, where ll is the two-letter language code, and CC is the two-letter country code.
Language codes consist of a pair of lowercase letters that conform to ISO-639.
Table 105. Sample Language Codes

Language Code | Description
de | German
en | English
es | Spanish
ja | Japanese

To see a full list of ISO-639 codes, go to http://www.ics.uci.edu/pub/ietf/http/related/iso639.txt.
Country codes consist of two uppercase letters that conform to ISO-3166.
Table 106. Sample Country Codes

Country Code | Description
DE | Germany
US | United States
ES | Spain
MX | Mexico
JP | Japan

A copy of ISO-3166 can be found at http://www.chemie.fu-berlin.de/diverse/doc/ISO_3166.html.
Combining with other attributes
The territory attribute is used only when creating a database.
In the following example, the new database has a territory of Spanish language and Mexican nationality.

    jdbc:derby:MexicanDB;create=true;territory=es_MX

You can use the collation attribute with the territory attribute to specify that collation is based on the territory instead of based on Unicode codepoint collation,
user=userName attribute
Specifies a valid user name for the system, specified with a password. A valid user name and password are required when user authentication is turned on.
Combining with other attributes
Use in conjunction with the password=userPassword attribute.
The following database connection URL connects the user jill to toursDB:

    jdbc:derby:toursDB;user=jill;password=toFetchAPail

ssl=sslMode attribute
Function
Specifies the SSL mode of the client. The sslMode can be basic, peerAuthentication, or off (the default). See "Network encryption and authentication with SSL/TLS" in the Java DB Server and Administration Guide for details.
Combining with other attributes
May be combined with all other attributes.
Example
Connecting to mydb with basic SSL encryption:

    jdbc:derby://localhost/mydb;ssl=basic

Creating a connection without specifying attributes
If no attributes are specified, you must specify a databaseName.
Derby opens a connection to an existing database with that name in the current system directory. If the database does not exist, the connection attempt returns an SQLException indicating that the database cannot be found.

    jdbc:derby:mydb

J2EE Compliance: Java Transaction API and javax.sql Interfaces
J2EE, or the Java 2 Platform, Enterprise Edition, is a standard for development of enterprise applications based on reusable components in a multi-tier environment. In addition to the features of the Java 2 Platform, Standard Edition (J2SE) J2EE adds support for Enterprise Java Beans (EJBs), Java Server Pages (JSPs), Servlets, XML and many more. The J2EE architecture is used to bring together existing technologies and enterprise applications in a single, manageable environment.
Derby is a J2EE-conformant component in a distributed J2EE system. As such, Derby is one part of a larger system that includes, among other things, a JNDI server, a connection pool module, a transaction manager, a resource manager, and user applications. Within this system, Derby can serve as the resource manager.
For more information on J2EE, see the J2EE specification available at http://java.sun.com/javaee/reference/ .
In order to qualify as a resource manager in a J2EE system, J2EE requires these basic areas of support:

• |  | JNDI support Allows calling applications to register names for databases and access them through those names instead of through database connection URLs. Implementation of one of the JDBC interfaces, javax.sql.DataSource, provides this support.
• |  | Connection pooling A mechanism by which a connection pool server keeps a set of open connections to a resource manager (Derby). A user requesting a connection can get one of the available connections from the pool. Such a connection pool is useful in client/server environments because establishing a connection is relatively expensive. In an embedded environment, connections are much cheaper, making the performance advantage of a connection pool negligible. Implementation of two of the JDBC interfaces, javax.sql.ConnectionPoolDataSource and javax.sql.PooledConnection, provide this support.
• |  | XA support XA is one of several standards for distributed transaction management. It is based on two-phase commit. The javax.sql.XAxxx interfaces, along with java.transaction.xa package, are an abstract implementation of XA. For more information about XA, see X/Open CAE Specification-Distributed Transaction Processing: The XA Specification, X/Open Document No. XO/CAE/91/300 or ISBN 1 872630 24 3. Implementation of the JTA API, the interfaces of the java.transaction.xa package (javax.sql.XAConnection, javax.sql.XADataSource, javax.transaction.xa.XAResource, javax.transaction.xa.Xid, and javax.transaction.xa.XAException), provides this support.

With the exception of the core JDBC interfaces, these interfaces are not visible to the end-user application; instead, they are used only by the other back-end components in the system.
Note: For information on the classes that implement these interfaces and how to use Derby as a resource manager, see Chapter 6, "Using Derby as a J2EE Resource Manager" in the Java DB Developer's Guide.
The JTA API
The JTA API is made up of the two interfaces and one exception that are part of the java.transaction.xa package. Derby fully implements this API.

• |  | javax.transaction.xa.XAResource
• |  | javax.transaction.xa.Xid
• |  | javax.transaction.xa.XAException

Notes on Product Behavior
Recovered Global Transactions
Using the XAResource.prepare call causes a global transaction to enter a prepared state, which allows it to be persistent. Typically, the prepared state is just a transitional state before the transaction outcome is determined. However, if the system crashes, recovery puts transactions in the prepared state back into that state and awaits instructions from the transaction manager.
XAConnections, user names and passwords
If a user opens an XAConnection with a user name and password, the transaction it created cannot be attached to an XAConnection opened with a different user name and password. A transaction created with an XAConnection without a user name and password can be attached to any XAConnection.
However, the user name and password for recovered global transactions are lost; any XAConnection can commit or roll back that in-doubt transaction.
Note: Use the network client driver's XA DataSource interface (org.apache.derby.jdbc.ClientXADataSource) when XA support is required in a remote (client/server) environment.
javax.sql: JDBC Interfaces
This section documents the JDBC interfaces that Derby implements for J2EE compliance.
For more details about these interfaces, see the API documentation for your version of the Java Development Kit, which you can find at http://java.sun.com/javase/reference/api.jsp.

• |  | javax.sql.DataSource An interface that is a factory for connections to the physical data source that the object represents. An object that implements the DataSource interface will typically be registered with a naming service based on the Java Naming and Directory (JNDI) API.
• |  | javax.sql.ConnectionPoolDataSource and javax.sql.PooledConnection Establishing a connection to the database can be a relatively expensive operation in client/server environments. Establishing the connection once and then using the same connection for multiple requests can dramatically improve the performance of a database. The Derby implementation of ConnectionPoolDataSource and PooledConnection interfaces allows a connection pool server to maintain a set of such connections to the resource manager (Derby). In an embedded environment, connections are much cheaper and connection pooling is not necessary.
• |  | javax.sql.XAConnection An XAConnection produces an XAResource, and, over its lifetime, many Connections. This type of connection allows for distributed transactions.
• |  | javax.sql.XADataSource An XADataSource is simply a ConnectionPoolDataSource that produces XAConnections.

In addition, Derby provides three methods for XADataSource, DataSource, and ConnectionPoolDataSource. Derby supports a number of additional data source properties:

• |  | setCreateDatabase(String create) Sets a property to create a database at the next connection. The string argument must be "create".
• |  | setShutdownDatabase(String shutdown) Sets a property to shut down a database. Shuts down the database at the next connection. The string argument must be "shutdown".

Note: Set these properties before getting the connection.
Derby API
Derby provides Javadoc HTML files of API classes and interfaces in the javadoc subdirectory.
This appendix provides a brief overview of the API. Derby does not provide the Javadoc for the java.sql packages, the main API for working with Derby, because it is included in the JDBC API. For information about Derby's implementation of JDBC, see JDBC reference.
This document divides the API classes and interfaces into several categories. The stand-alone tools and utilities are java classes that stand on their own and are invoked in a command window. The JDBC implementation classes are standard JDBC APIs, and are not invoked on the command-line. Instead, you invoke these only within a specified context within another application.
Stand-alone tools and utilities
These classes are in the packages org.apache.derby.tools.

• |  | org.apache.derby.tools.ij An SQL scripting tool that can run as an embedded or a remote client/server application. See the Java DB Tools and Utilities Guide.
• |  | org.apache.derby.tools.sysinfo A command-line, server-side utility that displays information about your JVM and Derby product. See the Java DB Tools and Utilities Guide.
• |  | org.apache.derby.tools.dblook A utility to view all or parts of the Data Definition Language (DDL) for a given database. See the Java DB Tools and Utilities Guide.

JDBC implementation classes
JDBC driver
This is the JDBC driver for Derby:

• |  | org.apache.derby.jdbc.EmbeddedDriver Used to boot the embedded built-in JDBC driver and the Derby system.
• |  | org.apache.derby.jdbc.ClientDriver Used to connect to the Derby Network Server in client-server mode.

See the Java DB Developer's Guide.
Data Source Classes
These classes are all related to Derby's implementation of javax.sql.DataSource and related APIs. For more information, see the Java DB Developer's Guide.
Each of these classes has two variants. Use the first variant if your application runs on JDK 1.5 or lower. Use the second variant (the one ending in "40") if your application runs on JDK 1.6 or higher.
Embedded environment:

• |  | org.apache.derby.jdbc.EmbeddedDataSource and org.apache.derby.jdbc.EmbeddedDataSource40
• |  | org.apache.derby.jdbc.EmbeddedConnectionPoolDataSource and org.apache.derby.jdbc.EmbeddedConnectionPoolDataSource40
• |  | org.apache.derby.jdbc.EmbeddedXADataSource and org.apache.derby.jdbc.EmbeddedXADataSource40

Client-server environment

• |  | org.apache.derby.jdbc.ClientDataSource and org.apache.derby.jdbc.ClientDataSource40
• |  | org.apache.derby.jdbc.ClientConnectionPoolDataSource and org.apache.derby.jdbc.ClientConnectionPoolDataSource40
• |  | org.apache.derby.jdbc.ClientXADataSource and org.apache.derby.jdbc.ClientXADataSource40

Miscellaneous utilities and interfaces

• |  | org.apache.derby.authentication.UserAuthenticator
• |  | An interface provided by Derby. Classes that provide an alternate user authentication scheme must implement this interface. For information about users, see "Working with User Authentication" in Chapter 7 of the Java DB Developer's Guide.

Supported territories
The following is a list of supported territories:

Territory | Derby territory setting (derby.territory)
Chinese (Simplified) | zh_CN
Chinese (Traditional) | zh_TW
Czech | cs
French | fr
German | de_DE
Hungarian | hu
Italian | it
Japanese | ja_JP
Korean | ko_KR
Polish | pl
Portuguese (Brazilian) | pt_BR
Russian | ru
Spanish | es

Derby limitations
The section lists the limitations associated with Derby.
Limitations for database manager values
Table 107. Database manager limitations
The following table lists limitations on various Database Manager values in Derby.

Value | Limit
Maximum columns in a table | 1,012
Maximum columns in a view | 5,000
Maximum number of parameters in a stored procedure | 90
Maximum indexes on a table | 32,767 or storage capacity
Maximum tables referenced in an SQL statement or a view | storage capacity
Maximum elements in a select list | 1,012
Maximum predicates in a WHERE or HAVING clause | storage capacity
Maximum number of columns in a GROUP BY clause | 32,677
Maximum number of columns in an ORDER BY clause | 1,012
Maximum number of prepared statements | storage capacity
Maximum declared cursors in a program | storage capacity
Maximum number of cursors opened at one time | storage capacity
Maximum number of constraints on a table | storage capacity
Maximum level of subquery nesting | storage capacity
Maximum number of subqueries in a single statement | storage capacity
Maximum number of rows changed in a unit of work | storage capacity
Maximum constants in a statement | storage capacity
Maximum depth of cascaded triggers | 16

DATE, TIME, and TIMESTAMP limitations
The following table lists limitations on date, time, and timestamp values in Derby.
Table 108. DATE, TIME, and TIMESTAMP limitations

Value | Limit
Smallest DATE value | 0001-01-01
Largest DATE value | 9999-12-31
Smallest TIME value | 00:00:00
Largest TIME value | 24:00:00
Smallest TIMESTAMP value | 0001-01-01-00.00.00.000000
Largest TIMESTAMP value | 9999-12-31-23.59.59.999999

Limitations on identifier length
Table 109. Identifier length limitations
The following table lists limitations on identifier lengths in Derby.

Identifier | Maximum number of characters allowed
constraint name | 128
correlation name | 128
cursor name | 128
data source column name | 128
data source index name | 128
data source name | 128
savepoint name | 128
schema name | 128
unqualified column name | 128
unqualified function name | 128
unqualified index name | 128
unqualified procedure name | 128
parameter name | 128
unqualified trigger name | 128
unqualified table name, view name, stored procedure name | 128

Numeric limitations
There are limitations on the numeric values in Derby.
Table 110. Numeric limitations

Value | Limit
Smallest INTEGER | -2,147,483,648
Largest INTEGER | 2,147,483,647
Smallest BIGINT | -9,223,372,036,854,775,808
Largest BIGINT | 9,223,372,036,854,775,807
Smallest SMALLINT | -32,768
Largest SMALLINT | 32,767
Largest decimal precision | 31
Smallest DOUBLE | -1.79769E+308
Largest DOUBLE | 1.79769E+308
Smallest positive DOUBLE | 2.225E-307
Largest negative DOUBLE | -2.225E-307
Smallest REAL | -3.402E+38
Largest REAL | 3.402E+38
Smallest positive REAL | 1.175E-37
Largest negative REAL | -1.175E-37

String limitations
Table 111. String limitations
The following table contains limitations on string values in Derby.

Value | Maximum Limit
Length of CHAR | 254 characters
Length of VARCHAR | 32,672 characters
Length of LONG VARCHAR | 32,700 characters
Length of CLOB | 2,147,483,647 characters
Length of BLOB | 2,147,483,647 characters
Length of character constant | 32,672
Length of concatenated character string | 2,147,483,647
Length of concatenated binary string | 2,147,483,647
Number of hex constant digits | 16,336
Length of DOUBLE value constant | 30 characters

XML limitations
The following table lists the limitations on XML data types in Derby.
Table 112. XML limitations

Issue | Limitation
Length of XML | 2,147,483,647 characters
Use of XML operators | Requires that the JAXP parser classes, such as Apache Xerces, and Apache Xalan classes are in the classpath. Attempts to use XML operators without these classes in the classpath results in an error.

Trademarks
The following terms are trademarks or registered trademarks of other companies and have been used in at least one of the documents in the Apache Derby documentation library:
Cloudscape, DB2, DB2 Universal Database, DRDA, and IBM are trademarks of International Business Machines Corporation in the United States, other countries, or both.
Microsoft, Windows, Windows NT, and the Windows logo are trademarks of Microsoft Corporation in the United States, other countries, or both.
Java and all Java-based trademarks are trademarks of Sun Microsystems, Inc. in the United States, other countries, or both.
UNIX is a registered trademark of The Open Group in the United States and other countries.
Other company, product, or service names may be trademarks or service marks of others.
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