X-Original-To: pgsql-docs-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 36C448B9C0C for ; Wed, 2 Feb 2005 10:02:55 +0000 (GMT) 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 85669-10 for ; Wed, 2 Feb 2005 10:02:49 +0000 (GMT) Received: from smtp.dkm.cz (smtp.dkm.cz [62.24.64.34]) by svr1.postgresql.org (Postfix) with SMTP id 198B08B9D11 for ; Wed, 2 Feb 2005 10:02:49 +0000 (GMT) Received: (qmail 29822 invoked by uid 0); 2 Feb 2005 10:02:47 -0000 Received: from r2g224.chello.upc.cz (HELO smradoch.ath.cx) (62.245.70.224) by smtp.dkm.cz with SMTP; 2 Feb 2005 10:02:46 -0000 Received: by smradoch.ath.cx (Postfix, from userid 1001) id A44F11F87BEE; Wed, 2 Feb 2005 11:02:46 +0100 (CET) Date: Wed, 2 Feb 2005 11:02:46 +0100 From: Roman Neuhauser To: pgsql-docs@postgresql.org Subject: planner stats Message-ID: <20050202100246.GA1859@isis.wad.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.6i X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.222 tagged_above=0 required=5 tests=AWL, FORGED_RCVD_HELO X-Spam-Level: X-Archive-Number: 200502/5 X-Sequence-Number: 2838 Hello, trying to figure out the right statistics target for a large table, I found the reference manual lacking: the SET STATISTICS description under ALTER TABLE doesn't explain how to choose the right target (is there a formula?), I'm not insisting it should, but: it says "For more information on the use of statistics by the PostgreSQL query planner, refer to Section 13.2.", but that section *doesn't* talk about "the use of statistics by the query planner"; it doesn't hint a method to choose a good target either (the page can be summed up to: "it's there, it influences the planner, you can change it through this mechanism, access it that way"). runtime-config.html#GUC-DEFAULT-STATISTICS-TARGET also misdirects the reader to 13.2. -- FreeBSD 4.10-STABLE 10:48AM up 3:53, 4 users, load averages: 0.00, 0.00, 0.00