Look at peter eisentraut's procedural language PL/sh
It's on pgfoundry.
... John
> -----Original Message-----
> From: pgsql-hackers-owner@postgresql.org
> [mailto:pgsql-hackers-owner@postgresql.org] On Behalf Of Tom Lane
> Sent: Saturday, June 04, 2005 5:16 AM
> To: Gevik babakhani
> Cc: pgsql-hackers@postgresql.org
> Subject: Re: [HACKERS] executing OS programs from pg
>
> "Gevik babakhani" <gevik@xs4all.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
>
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