X-Original-To: pgsql-performance-postgresql.org@postgresql.org Received: from localhost (wm.hub.org [200.46.204.128]) by postgresql.org (Postfix) with ESMTP id 4678B9FB24B for ; Tue, 29 Aug 2006 11:46:55 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.128]) (amavisd-new, port 10024) with ESMTP id 25333-04 for ; Tue, 29 Aug 2006 14:46:42 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey- Received: from moutng.kundenserver.de (moutng.kundenserver.de [212.227.126.177]) by postgresql.org (Postfix) with ESMTP id CF7FC9FB227 for ; Tue, 29 Aug 2006 11:46:39 -0300 (ADT) Received: from [194.25.154.138] (helo=webserv.wug.de) by mrelayeu.kundenserver.de (node=mrelayeu4) with ESMTP (Nemesis), id 0ML21M-1GI4rN38IN-0002fP; Tue, 29 Aug 2006 16:46:38 +0200 Received: from kretschmer by webserv.wug.de with local (Exim 3.36 #1) id 1GI4rM-0001sX-00 for pgsql-performance@postgresql.org; Tue, 29 Aug 2006 16:46:36 +0200 Date: Tue, 29 Aug 2006 16:46:36 +0200 From: "A. Kretschmer" To: pgsql-performance@postgresql.org Subject: Re: PostgreSQL performance issues Message-ID: <20060829144636.GA6796@localhost.localdomain> References: <44F446B2.2090900@studentvillage.co.za> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <44F446B2.2090900@studentvillage.co.za> User-Agent: Mutt/1.5.9i X-Provags-ID: kundenserver.de abuse@kundenserver.de login:51ea9561fc3f6d9539a2acd743e4748c X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200608/454 X-Sequence-Number: 20639 am Tue, dem 29.08.2006, um 15:52:50 +0200 mailte Willo van der Merwe folgendes: > and it has 743321 rows and a explain analyze select count(*) from > property_values; > QUERY > PLAN > ---------------------------------------------------------------------------------------------------------------------------------- > Aggregate (cost=55121.95..55121.96 rows=1 width=0) (actual time= > 4557.797..4557.798 rows=1 loops=1) > -> Seq Scan on property_values (cost=0.00..51848.56 rows=1309356 width=0) > (actual time=0.026..2581.418 rows=1309498 loops=1) > Total runtime: 4557.978 ms > (3 rows) > > 4 1/2 seconds for a count(*) ? This seems a bit rough - is there anything else Because of MVCC. http://www.thescripts.com/forum/thread173678.html http://www.varlena.com/GeneralBits/120.php http://www.varlena.com/GeneralBits/49.php Andreas -- Andreas Kretschmer Kontakt: Heynitz: 035242/47215, D1: 0160/7141639 (mehr: -> Header) GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net