"Gevik babakhani" <gevik(at)xs4all(dot)nl> writes:
> Does anyone know how to execute an OS command from pgsql. I would like to
> create a trigger that op on firing would run/execute an external program.

Use any of the "untrusted" PLs to execute system() or the like.

Whether this is a good idea or not is a different question --- there are
excellent reasons why it is a *bad* idea to execute outside-the-database
actions from within a trigger.  Mainly that the actions won't be undone
if the transaction later rolls back, and now your database state is
inconsistent with outside-the-database state.  See the list archives for
many past discussions of this point and safer ways to design your
application.

(BTW, this is hardly material for -hackers.)

			regards, tom lane

In response to

• executing OS programs from pg at 2005-06-03 18:56:44 from Gevik babakhani

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