X-Original-To: pgsql-sql-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 11B7BD1B17B for ; Tue, 29 Jun 2004 14:33:36 -0300 (ADT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 09336-05 for ; Tue, 29 Jun 2004 17:33:35 +0000 (GMT) Received: from stark.xeocode.com (gsstark.mtl.istop.com [66.11.160.162]) by svr1.postgresql.org (Postfix) with ESMTP id C9E15D1B170 for ; Tue, 29 Jun 2004 14:33:33 -0300 (ADT) Received: from localhost ([127.0.0.1] helo=stark.xeocode.com) by stark.xeocode.com with smtp (Exim 3.36 #1 (Debian)) id 1BfMTz-0003gx-00; Tue, 29 Jun 2004 13:33:23 -0400 To: Stephan Szabo Cc: Stefan Weiss , pgsql-sql@postgresql.org Subject: Re: FW: "=" operator vs. "IS" References: <7A4ADADFC8AFF0478D47F63BEDD57CE33A320C@gpmail.gphq.genpathpharma.com> <200406290102.24885.spaceman@foo.at> <20040628161747.C38283@megazone.bigpanda.com> In-Reply-To: <20040628161747.C38283@megazone.bigpanda.com> From: Greg Stark Organization: The Emacs Conspiracy; member since 1992 Date: 29 Jun 2004 13:33:23 -0400 Message-ID: <873c4ez2u4.fsf@stark.xeocode.com> Lines: 13 User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.0 tagged_above=0.0 required=5.0 tests= X-Spam-Level: X-Archive-Number: 200406/299 X-Sequence-Number: 18244 Stephan Szabo writes: > IS TRUE and IS FALSE have a different effect from =true and =false when > the left hand side is NULL. The former will return false, the latter will > return NULL. No, actually they both return false. (But thanks, I didn't even realize they were special this way) -- greg