Received: from sss.pgh.pa.us (sss.pgh.pa.us [216.151.103.158])
	by postgresql.org (8.11.3/8.11.1) with ESMTP id f3UFOZ319698;
	Mon, 30 Apr 2001 11:24:35 -0400 (EDT)
	(envelope-from tgl@sss.pgh.pa.us)
Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1])
	by sss.pgh.pa.us (8.11.3/8.11.3) with ESMTP id f3UEOOR14770;
	Mon, 30 Apr 2001 10:24:24 -0400 (EDT)
To: Sandro Dentella <sandro.dentella@tin.it>
cc: pgsql-interfaces@postgresql.org, pgsql-docs@postgresql.org
Subject: Re: [INTERFACES] function returning NULL? 
In-reply-to: <20010430105600.B6311@bluff.ermit.it> 
References: <20010430105600.B6311@bluff.ermit.it>
Comments: In-reply-to Sandro Dentella <sandro.dentella@tin.it>
	message dated "Mon, 30 Apr 2001 10:56:00 +0200"
Date: Mon, 30 Apr 2001 10:24:24 -0400
Message-ID: <14767.988640664@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
X-Archive-Number: 200104/98
X-Sequence-Number: 670

Sandro Dentella <sandro.dentella@tin.it> writes:
> I'm trying to create a function that should return a date, and occasionally
> NULL value. I can't see how to do that. I'm using pl/tcl.

You need the "return_null" command, which is new in 7.1 --- before that
there was no way to do it in pltcl.

"return_null" seems to be missing from the documentation :-(.  No wonder
you couldn't find it.

			regards, tom lane