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 04FB0329CDB for ; Tue, 21 Sep 2004 19:26:42 +0100 (BST) 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 34686-03 for ; Tue, 21 Sep 2004 18:26:39 +0000 (GMT) Received: from stark.xeocode.com (gsstark.mtl.istop.com [66.11.160.162]) by svr1.postgresql.org (Postfix) with ESMTP id 87A51329CD2 for ; Tue, 21 Sep 2004 19:26:39 +0100 (BST) Received: from localhost ([127.0.0.1] helo=stark.xeocode.com) by stark.xeocode.com with smtp (Exim 3.36 #1 (Debian)) id 1C9pLZ-0007zw-00; Tue, 21 Sep 2004 14:26:37 -0400 To: Tom Lane Cc: "Dean Gibson (DB Administrator)" , pgsql-sql@postgresql.org Subject: Re: JOIN performance References: <5.1.0.14.2.20040920121606.00a89c68@imaps.mailpen.net> <414F02FF.8000603@numerixtechnology.de> <414F02FF.8000603@numerixtechnology.de> <5.1.0.14.2.20040920121606.00a89c68@imaps.mailpen.net> <5.1.0.14.2.20040920164348.00a99868@imaps.mailpen.net> <23901.1095728070@sss.pgh.pa.us> In-Reply-To: <23901.1095728070@sss.pgh.pa.us> From: Greg Stark Organization: The Emacs Conspiracy; member since 1992 Date: 21 Sep 2004 14:26:37 -0400 Message-ID: <87oejzeaw2.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: 200409/195 X-Sequence-Number: 19041 Tom Lane writes: > Fixing this properly is a research project, and I haven't thought of any > quick-and-dirty hacks that aren't too ugly to consider :-( Just thinking out loud here. Instead of trying to peek inside the CASE couldn't the optimizer just wrap the non-strict expression in a conditional that tests whether the row was found? -- greg