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DBLINK_FETCH(3)		PostgreSQL 9.6.3 Documentation	       DBLINK_FETCH(3)

NAME
       dblink_fetch - returns rows from	an open	cursor in a remote database

SYNOPSIS
       dblink_fetch(text cursorname, int howmany [, bool fail_on_error]) returns setof record
       dblink_fetch(text connname, text	cursorname, int	howmany	[, bool	fail_on_error])	returns	setof record

DESCRIPTION
       dblink_fetch fetches rows from a	cursor previously established by
       dblink_open.

ARGUMENTS
       connname
	   Name	of the connection to use; omit this parameter to use the
	   unnamed connection.

       cursorname
	   The name of the cursor to fetch from.

       howmany
	   The maximum number of rows to retrieve. The next howmany rows are
	   fetched, starting at	the current cursor position, moving forward.
	   Once	the cursor has reached its end,	no more	rows are produced.

       fail_on_error
	   If true (the	default	when omitted) then an error thrown on the
	   remote side of the connection causes	an error to also be thrown
	   locally. If false, the remote error is locally reported as a
	   NOTICE, and the function returns no rows.

RETURN VALUE
       The function returns the	row(s) fetched from the	cursor.	To use this
       function, you will need to specify the expected set of columns, as
       previously discussed for	dblink.

NOTES
       On a mismatch between the number	of return columns specified in the
       FROM clause, and	the actual number of columns returned by the remote
       cursor, an error	will be	thrown.	In this	event, the remote cursor is
       still advanced by as many rows as it would have been if the error had
       not occurred. The same is true for any other error occurring in the
       local query after the remote FETCH has been done.

EXAMPLES
	   SELECT dblink_connect('dbname=postgres');
	    dblink_connect
	   ----------------
	    OK
	   (1 row)

	   SELECT dblink_open('foo', 'select proname, prosrc from pg_proc where	proname	like ''bytea%''');
	    dblink_open
	   -------------
	    OK
	   (1 row)

	   SELECT * FROM dblink_fetch('foo', 5)	AS (funcname name, source text);
	    funcname |	source
	   ----------+----------
	    byteacat | byteacat
	    byteacmp | byteacmp
	    byteaeq  | byteaeq
	    byteage  | byteage
	    byteagt  | byteagt
	   (5 rows)

	   SELECT * FROM dblink_fetch('foo', 5)	AS (funcname name, source text);
	    funcname  |	 source
	   -----------+-----------
	    byteain   |	byteain
	    byteale   |	byteale
	    bytealike |	bytealike
	    bytealt   |	bytealt
	    byteane   |	byteane
	   (5 rows)

	   SELECT * FROM dblink_fetch('foo', 5)	AS (funcname name, source text);
	     funcname  |   source
	   ------------+------------
	    byteanlike | byteanlike
	    byteaout   | byteaout
	   (2 rows)

	   SELECT * FROM dblink_fetch('foo', 5)	AS (funcname name, source text);
	    funcname | source
	   ----------+--------
	   (0 rows)

PostgreSQL 9.6.3		     2017		       DBLINK_FETCH(3)

NAME | SYNOPSIS | DESCRIPTION | ARGUMENTS | RETURN VALUE | NOTES | EXAMPLES

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