X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 2C3AA5284F for ; Sun, 29 May 2005 10:47:16 -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 66221-04 for ; Sun, 29 May 2005 13:47:13 +0000 (GMT) Received: from cassarossa.samfundet.no (cassarossa.samfundet.no [129.241.93.19]) by svr1.postgresql.org (Postfix) with ESMTP id 7B59F5284B for ; Sun, 29 May 2005 10:47:12 -0300 (ADT) Received: from trofast.sesse.net ([129.241.93.32]) by cassarossa.samfundet.no with esmtp (Exim 4.34) id 1DcO8H-0000mq-W3 for pgsql-performance@postgresql.org; Sun, 29 May 2005 15:47:15 +0200 Received: from sesse by trofast.sesse.net with local (Exim 3.36 #1 (Debian)) id 1DcO8H-0000rB-00 for ; Sun, 29 May 2005 15:47:13 +0200 Date: Sun, 29 May 2005 15:47:13 +0200 From: "Steinar H. Gunderson" To: pgsql-performance@postgresql.org Subject: Re: sequential scan performance Message-ID: <20050529134712.GA2987@uio.no> Mail-Followup-To: pgsql-performance@postgresql.org References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-Operating-System: Linux 2.6.11.8 on a i686 X-Message-Flag: Outlook? --> http://www.mozilla.org/products/thunderbird/ User-Agent: Mutt/1.5.9i X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.013 tagged_above=0 required=5 tests=AWL X-Spam-Level: X-Archive-Number: 200505/420 X-Sequence-Number: 12584 On Sun, May 29, 2005 at 08:27:26AM -0500, Michael Engelhart wrote: > this is a query that our system needs to do a LOT. Is there any way > to improve the performance on this either with changes to our query > or by configuring the database deployment? We have an index on > city_name but when using the % operator on the front of the query > string postgresql can't use the index . Try tsearch2 from contrib, it might help you. /* Steinar */ -- Homepage: http://www.sesse.net/