# 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
- Aggregates (set functions)
- ABS or ABSVAL function
- ACOS function
  The ACOS function returns the arc cosine of a specified number.
- ASIN function
  The ASIN function returns the arc sine of a specified number.
- ATAN function
  The ATAN function returns the arc tangent of a specified number.
- AVG function
- BIGINT function
- CASE expressions
  Use the CASE expressions for conditional expressions in Derby.
- 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.
- 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.
- CHAR function
  The CHAR function returns a fixed-length character string representation.
- Concatenation operator
- COS function
  The COS function returns the cosine of a specified number.
- 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
  The DATE function returns a date from a value.
- DAY function
  The DAY function returns the day part of a value.
- DEGREES function
  The DEGREES function converts a specified number from radians to degrees.
- DOUBLE function
- EXP function
  The EXP function returns e raised to the power of the specified 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.
- HOUR function
  The HOUR function returns the hour part of a value.
- IDENTITY_VAL_LOCAL function
- INTEGER function
- LCASE or LOWER function
- LENGTH function
- LN or LOG function
  The LN and LOG functions return the natural logarithm (base e) of the specified number.
- LOG10 function
  The LOG10 function returns the base-10 logarithm of the specified number.
- LOCATE function
- LTRIM function
- MAX function
- MIN function
- MINUTE function
  The MINUTE function returns the minute part of a value.
- MOD function
- MONTH function
  The MONTH function returns the month part of a value.
- NULLIF expressions
  Use the NULLIF expressions for conditional expressions in Derby.
- PI function
  The PI function returns a value that is closer than any other value to pi.
- RADIANS function
  The RADIANS function converts a specified number from degrees to radians.
- RTRIM function
- SECOND function
  The SECOND function returns the seconds part of a value.
- SESSION_USER function
- SIN function
  The SIN function returns the sine of a specified number.
- SMALLINT function
- SQRT function
- SUBSTR function
- SUM function
- TAN function
  The TAN function returns the tangent of a specified number.
- TIME function
  The TIME function returns a time from a value.
- TIMESTAMP function
  The TIMESTAMP function returns a timestamp from a value or a pair of values.
- TRIM function
- UCASE or UPPER function
- USER function
- VARCHAR function
- XMLEXISTS operator
  XMLEXISTS is an SQL/XML operator that you can use to query XML values in SQL.
- XMLPARSE operator
  XMLPARSE is a SQL/XML operator that you use to parse a character string expression into a Derby XML value.
- XMLQUERY operator
  XMLQUERY is a SQL/XML operator that you can use to query XML values in SQL.
- 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.
- YEAR function

Parent topic: SQL language reference
Related concepts
SQL identifiers
Statements
Built-in system functions
Built-in system procedures
Data types
Related reference
Capitalization and special characters
SQL clauses
SQL expressions
JOIN operations
SQL queries
SYSCS_DIAG diagnostic tables and functions