dblink_open(3) PostgreSQL 9.4.15 Documentation dblink_open(3)
NAME
dblink_open - opens a cursor in a remote database
SYNOPSIS
dblink_open(text cursorname, text sql [, bool fail_on_error]) returns text
dblink_open(text connname, text cursorname, text sql [, bool fail_on_error]) returns text
DESCRIPTION
dblink_open(3) opens a cursor in a remote database. The cursor can
subsequently be manipulated with dblink_fetch() and dblink_close().
ARGUMENTS
connname
Name of the connection to use; omit this parameter to use the
unnamed connection.
cursorname
The name to assign to this cursor.
sql
The SELECT statement that you wish to execute in the remote
database, for example select * from pg_class.
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's return value is set to ERROR.
RETURN VALUE
Returns status, either OK or ERROR.
NOTES
Since a cursor can only persist within a transaction, dblink_open
starts an explicit transaction block (BEGIN) on the remote side, if the
remote side was not already within a transaction. This transaction will
be closed again when the matching dblink_close is executed. Note that
if you use dblink_exec to change data between dblink_open and
dblink_close, and then an error occurs or you use dblink_disconnect
before dblink_close, your change will be lost because the transaction
will be aborted.
EXAMPLES
SELECT dblink_connect('dbname=postgres');
dblink_connect
----------------
OK
(1 row)
SELECT dblink_open('foo', 'select proname, prosrc from pg_proc');
dblink_open
-------------
OK
(1 row)
PostgreSQL 9.4.15 2017 dblink_open(3)
PostgreSQL 9.4.15 - Generated Wed Nov 29 18:36:44 CST 2017