Berkeley DB Reference Guide: Cursor operations
Description: Berkeley DB: An embedded database programmatic toolkit.
Keywords: embedded,database,programmatic,toolkit,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++

### Berkeley DB Reference Guide: Access Methods |

### Cursor operations

A database cursor refers to a single key/data pair in the database. It supports traversal of the database and is the only way to access individual duplicate data items. Cursors are used for operating on collections of records, for iterating over a database, and for saving handles to individual records, so that they can be modified after they have been read.

The DB->cursor method opens a cursor into a database. Upon return the cursor is uninitialized, cursor positioning occurs as part of the first cursor operation.

Once a database cursor has been opened, records may be retrieved (DBcursor->c_get), stored (DBcursor->c_put), and deleted (DBcursor->c_del).

Additional operations supported by the cursor handle include duplication (DBcursor->c_dup), equality join (DB->join), and a count of duplicate data items (DBcursor->c_count). Cursors are eventually closed using DBcursor->c_close.

Database Cursors and Related Methods | Description
--- | ---
DB->cursor | Create a cursor
DBcursor->c_close | Close a cursor
DBcursor->c_count | Return count of duplicates
DBcursor->c_del | Delete by cursor
DBcursor->c_dup | Duplicate a cursor
DBcursor->c_get, DBcursor->c_pget | Retrieve by cursor
DBcursor->c_put | Store by cursor

Copyright (c) 1996-2006 Oracle Corporation - All rights reserved.