X-Original-To: pgsql-sql-postgresql.org@localhost.postgresql.org Received: from localhost (neptune.hub.org [200.46.204.2]) by svr1.postgresql.org (Postfix) with ESMTP id 4B58CD1B440 for ; Sat, 29 Nov 2003 18:28:23 +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 38476-10 for ; Sat, 29 Nov 2003 14:27:58 -0400 (AST) Received: from joeconway.com (66-146-172-86.skyriver.net [66.146.172.86]) by svr1.postgresql.org (Postfix) with ESMTP id 4FE29D1B437 for ; Sat, 29 Nov 2003 14:27:51 -0400 (AST) Received: from [192.168.5.3] (account jconway HELO joeconway.com) by joeconway.com (CommuniGate Pro SMTP 4.1.8) with ESMTP-TLS id 692000; Sat, 29 Nov 2003 10:25:43 -0800 Message-ID: <3FC8E4B6.8030901@joeconway.com> Date: Sat, 29 Nov 2003 10:25:58 -0800 From: Joe Conway User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.3) Gecko/20030312 X-Accept-Language: en-us, en MIME-Version: 1.0 To: ow Cc: jasiek , pgsql-sql@postgresql.org Subject: Re: Seq Scans when index expected to be used References: <20031129180159.91794.qmail@web21404.mail.yahoo.com> In-Reply-To: <20031129180159.91794.qmail@web21404.mail.yahoo.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: by amavisd-new at postgresql.org X-Archive-Number: 200311/348 X-Sequence-Number: 16163 ow wrote: > My impression was that the index "I_bca" covers the query, hence there should > not be a need to go to the table itself. Why would it? Postgres always has to go to the table. The ability to read data directly from indexes (ala other RDBMSs) has been discussed, but not implemented. IIRC it's a hard problem due to the way Postgres does MVCC. Check the archives. > explain analyze vs explain. Normally, would've used "explain analyze" but in > this case it's taking way too long so I used "explain". I can understand that, but most people will ask for explain analyze anyway ;-) Joe