Received: from localhost (maia-2.hub.org [200.46.204.187]) by postgresql.org (Postfix) with ESMTP id 14D2D9FBC6F for ; Fri, 9 Mar 2007 12:02:28 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.187]) (amavisd-new, port 10024) with ESMTP id 56853-07 for ; Fri, 9 Mar 2007 12:02:18 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey-1.7.4 Received: from main2.mycybernet.net (main2.mycybernet.net [209.222.63.140]) by postgresql.org (Postfix) with ESMTP id 4D5DB9FBC18 for ; Fri, 9 Mar 2007 12:02:18 -0400 (AST) Received: from 227-54-222-209.mycybernet.net ([209.222.54.227] helo=phlogiston.dydns.org) by main2.mycybernet.net with esmtp (Exim 4.62) (envelope-from ) id 1HPhnM-0008Po-Q2 for pgsql-sql@postgresql.org; Fri, 09 Mar 2007 11:18:16 -0500 Received: by phlogiston.dydns.org (Postfix, from userid 1000) id DE2B83FAF; Fri, 9 Mar 2007 11:02:11 -0500 (EST) Date: Fri, 9 Mar 2007 11:02:11 -0500 From: Andrew Sullivan To: pgsql-sql@postgresql.org Subject: Re: index not being used. Why? Message-ID: <20070309160211.GA24502@phlogiston.dyndns.org> References: <45F176CA.3050107@fmed.uba.ar> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <45F176CA.3050107@fmed.uba.ar> User-Agent: Mutt/1.5.9i X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200703/114 X-Sequence-Number: 27752 On Fri, Mar 09, 2007 at 12:01:30PM -0300, Gerardo Herzig wrote: > Hi all. I have this 2 relations How big are they? > -> Hash (cost=9.08..9.08 rows=408 width=55) > -> Seq Scan on pages (cost=0.00..9.08 rows=408 width=55) The planner thinks it will get 408 rows. How big a percentage of the table is that? Also, what does EXPLAIN ANALYSE say about this? A -- Andrew Sullivan | ajs@crankycanuck.ca If they don't do anything, we don't need their acronym. --Josh Hamilton, on the US FEMA