Practical PostgreSQL

FETCH

Retrieves rows from a cursor.

Synopsis

FETCH direction
      [ count ] { IN | FROM } cursor

direction ::= { FORWARD | BACKWARD | RELATIVE }
count ::= { numrows | ALL | NEXT | PRIOR }

Parameters

direction

Use the optional direction parameter to specify the direction you want to fetch. It may be specified as any of the following keywords:

FORWARD

The keyword used to retrieve rows following the current position. This is the default, if the direction is not explicitly set.

BACKWARD

The keyword used to retrieve rows preceding the current position.

RELATIVE

A noise term made available for SQL92 compatibility. As of PostgreSQL 7.1.x, all cursors locate rows relative to the current cursor position, and this keyword therefore has no effect. Note that combining the RELATIVE keyword with a count of 0 will produce an error (see the “Results” section later in this reference entry).

count

This parameter takes the number of rows you wish to fetch. You can specify an integer constant here to have a specific number of rows fetched (numrows), or use any of the following keywords:

ALL

The keyword used to retrieve all rows.

NEXT

The keyword used to retrieve the row immediately following the current position.

PRIOR

The keyword used to retrieve the row immediately preceding the current position.

cursor

The name of an open cursor you wish to use for the FETCH.

Results

A successful FETCH command returns any query results generated by the specified cursor. If the query fails, one of the following messages will be displayed: ...