X-Original-To: pgsql-performance@postgresql.org Received: from spampd.localdomain (postgresql.org [64.49.215.8]) by postgresql.org (Postfix) with ESMTP id 7F4E847648D for ; Wed, 7 May 2003 11:27:28 -0400 (EDT) Received: from davinci.ethosmedia.com (unknown [209.10.40.251]) by postgresql.org (Postfix) with ESMTP id 60089475CE5 for ; Wed, 7 May 2003 11:26:59 -0400 (EDT) Received: from [63.195.55.98] (HELO spooky) by davinci.ethosmedia.com (CommuniGate Pro SMTP 4.0.2) with ESMTP id 3014883; Wed, 07 May 2003 08:27:04 -0700 Content-Type: text/plain; charset="iso-8859-1" From: Josh Berkus Organization: Aglio Database Solutions To: Achilleus Mantzios , Hannu Krosing Subject: Re: An unresolved performance problem. Date: Wed, 7 May 2003 08:26:52 -0700 User-Agent: KMail/1.4.3 Cc: pgsql-performance@postgresql.org References: In-Reply-To: MIME-Version: 1.0 Message-Id: <200305070826.52382.josh@agliodbs.com> Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, hits=-32.4 required=5.0 tests=BAYES_01,IN_REP_TO,QUOTED_EMAIL_TEXT,REFERENCES, REPLY_WITH_QUOTES,USER_AGENT_KMAIL autolearn=ham version=2.50 X-Spam-Level: X-Spam-Checker-Version: SpamAssassin 2.50 (1.173-2003-02-20-exp) X-Archive-Number: 200305/80 X-Sequence-Number: 1859 Achilleus, > My systems are (rather usual) linux/freebsd and the costs defined (by > default) in postgresql.conf worked well for all queries except > a cursed query on a cursed table. > So i start to believe its an estimation selectivity > problem. We can probably fix the problem by re-writing the query then; see my previ= ous=20 example this weekend about overdetermining criteria in order to force the u= se=20 of an index. How about posting the query and the EXPLAIN ANALYZE results? --=20 Josh Berkus Aglio Database Solutions San Francisco