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PostgreSQL 9.4.1 Documentation
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DECLARE

Name

DECLARE -- define a cursor

Synopsis

DECLAREcursor_name [ BINARY ] [ INSENSITIVE ] [ [ NO ] SCROLL ] CURSOR [ { WITH | WITHOUT } HOLD ] FORprepared_nameDECLAREcursor_name [ BINARY ] [ INSENSITIVE ] [ [ NO ] SCROLL ] CURSOR [ { WITH | WITHOUT } HOLD ] FORquery

Description

DECLARE declares a cursor for iterating over the result set of a prepared statement. This command has slightly different semantics from the direct SQL commandDECLARE: Whereas the latter executes a query and prepares the result set for retrieval, this embedded SQL command merely declares a name as a"loop variable" for iterating over the result set of a query; the actual execution happens when the cursor is opened with theOPEN command.

Parameters

cursor_name: A cursor name, case sensitive. This can be an SQL identifier or a host variable.
prepared_name: The name of a prepared query, either as an SQL identifier or a host variable.
query: ASELECT orVALUES command which will provide the rows to be returned by the cursor.

For the meaning of the cursor options, seeDECLARE.

Examples

Examples declaring a cursor for a query:

EXEC SQL DECLARE C CURSOR FOR SELECT * FROM My_Table;EXEC SQL DECLARE C CURSOR FOR SELECT Item1 FROM T;EXEC SQL DECLARE cur1 CURSOR FOR SELECT version();

An example declaring a cursor for a prepared statement:

EXEC SQL PREPARE stmt1 AS SELECT version();EXEC SQL DECLARE cur1 CURSOR FOR stmt1;

Compatibility

DECLARE is specified in the SQL standard.