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 C979052814 for ; Mon, 6 Jun 2005 13:41:24 -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 30848-05 for ; Mon, 6 Jun 2005 16:41:15 +0000 (GMT) Received: from boutiquenumerique.com (boutiquenumerique.com [82.67.9.10]) by svr1.postgresql.org (Postfix) with ESMTP id 577AB52806 for ; Mon, 6 Jun 2005 13:41:14 -0300 (ADT) Received: (qmail 16289 invoked from network); 6 Jun 2005 18:41:19 +0200 Received: from unknown (HELO localhost) (boutiquenumerique-lists@192.168.0.4) by boutiquenumerique.com with SMTP; 6 Jun 2005 18:41:19 +0200 To: "Amit V Shah" , "'Jeffrey Tenny'" , pgsql-performance@postgresql.org Subject: Re: Need help to decide Mysql vs Postgres References: <0C072E7CC947D511AC9600A0CC7341200256CF36@xeon400.tagaudit.com> Message-ID: Date: Mon, 06 Jun 2005 18:41:13 +0200 From: PFC Organization: =?iso-8859-15?Q?La_Boutique_Num=E9rique?= Content-Type: text/plain; format=flowed; delsp=yes; charset=iso-8859-15 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit In-Reply-To: <0C072E7CC947D511AC9600A0CC7341200256CF36@xeon400.tagaudit.com> User-Agent: Opera M2(BETA2)/8.0 (Linux, build 987) X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.006 tagged_above=0 required=5 tests=AWL X-Spam-Level: X-Archive-Number: 200506/119 X-Sequence-Number: 12756 > postgres -> returns results in 2.8 seconds What kind of plan does it do ? seq scan on the big tables and hash join on the small tables ? > mysql -> takes around 16 seconds !!!! (This is with myisam ... with > innodb it takes 220 seconds) I'm not surprised at all. Try the same Join query but with a indexed where + order by / limit on the big table and you should get even worse for MySQL. I found 3 tables in a join was the maximum the MySQL planner was able to cope with before blowing up just like you experienced. > I am all for postgres at this point, however just want to know why I am > getting opposite results !!! Both DBs are on the same machine Why do you say "opposite results" ?