Postgres-XC 0.9.7 Documentation
PrevFast BackwardFast ForwardNext

dblink_exec

Name

dblink_exec -- executes a command in a remote database

Synopsis

dblink_exec(text connname, text sql [, bool fail_on_error]) returns text
dblink_exec(text connstr, text sql [, bool fail_on_error]) returns text
dblink_exec(text sql [, bool fail_on_error]) returns text

Description

Note: The following description applies only to Postgres-XC

dblink module has not been tested with Postges-XC yet. Although there're no reason that dblink does not run in Postgres-XC, the development team leaves the test and the use of this module entirely to users.

This section is identical to the corresponding PostgreSQL reference manual.

Note: The following description applies only to PostgreSQL

dblink_exec executes a command (that is, any SQL statement that doesn't return rows) in a remote database.

When two text arguments are given, the first one is first looked up as a persistent connection's name; if found, the command is executed on that connection. If not found, the first argument is treated as a connection info string as for dblink_connect, and the indicated connection is made just for the duration of this command.

Arguments

Note: The following description applies only to PostgreSQL

conname

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

connstr

A connection info string, as previously described for dblink_connect.

sql

The SQL command that you wish to execute in the remote database, for example insert into foo values(0,'a','{"a0","b0","c0"}').

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

Note: The following description applies only to PostgreSQL

Returns status, either the command's status string or ERROR.

Example

Note: The following description applies only to PostgreSQL

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

SELECT dblink_exec('insert into foo values(21,''z'',''{"a0","b0","c0"}'');');
   dblink_exec
-----------------
 INSERT 943366 1
(1 row)

SELECT dblink_connect('myconn', 'dbname=regression');
 dblink_connect
----------------
 OK
(1 row)

SELECT dblink_exec('myconn', 'insert into foo values(21,''z'',''{"a0","b0","c0"}'');');
   dblink_exec
------------------
 INSERT 6432584 1
(1 row)

SELECT dblink_exec('myconn', 'insert into pg_class values (''foo'')',false);
NOTICE:  sql error
DETAIL:  ERROR:  null value in column "relnamespace" violates not-null constraint

 dblink_exec
-------------
 ERROR
(1 row)
PrevHomeNext
dblinkUpdblink_open