X-Original-To: pgsql-sql-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.2]) by svr1.postgresql.org (Postfix) with ESMTP id C786FD1D2E0 for ; Fri, 13 Feb 2004 01:22:54 +0000 (GMT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (neptune.hub.org [200.46.204.2]) (amavisd-new, port 10024) with ESMTP id 87461-07 for ; Thu, 12 Feb 2004 21:22:55 -0400 (AST) Received: from web60807.mail.yahoo.com (web60807.mail.yahoo.com [216.155.196.70]) by svr1.postgresql.org (Postfix) with SMTP id 09BB0D1D27C for ; Thu, 12 Feb 2004 21:22:51 -0400 (AST) Message-ID: <20040213012253.64419.qmail@web60807.mail.yahoo.com> Received: from [64.81.205.234] by web60807.mail.yahoo.com via HTTP; Thu, 12 Feb 2004 17:22:53 PST Date: Thu, 12 Feb 2004 17:22:53 -0800 (PST) From: ow Subject: Re: 7.4 - FK constraint performance To: Tom Lane Cc: pgsql-sql@postgresql.org In-Reply-To: <25808.1076634636@sss.pgh.pa.us> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Virus-Scanned: by amavisd-new at postgresql.org X-Archive-Number: 200402/126 X-Sequence-Number: 16817 --- Tom Lane wrote: > Can't see how we optimize your case without pessimizing more-common cases. My case appears to be pretty common, i.e. 1 small and 1 large table with RI constraint between them. In order to delete a record from the small table, the large table must not have records that are dependent on the deleted row. I think other RDBMSs simply use preset value instead of partial table scan when there's not enough stat info. Might be a better way. Thanks __________________________________ Do you Yahoo!? Yahoo! Finance: Get your refund fast by filing online. http://taxes.yahoo.com/filing.html