X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by postgresql.org (Postfix) with ESMTP id DA6FD9DC83E for ; Fri, 16 Dec 2005 01:20:28 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 06084-02 for ; Fri, 16 Dec 2005 01:20:27 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey- Received: from rwcrmhc12.comcast.net (rwcrmhc13.comcast.net [204.127.198.39]) by postgresql.org (Postfix) with ESMTP id B17089DC820 for ; Fri, 16 Dec 2005 01:20:26 -0400 (AST) Received: from sysexperts.com (c-67-170-228-241.hsd1.ca.comcast.net[67.170.228.241]) by comcast.net (rwcrmhc13) with ESMTP id <20051216052026015004ufe7e>; Fri, 16 Dec 2005 05:20:26 +0000 Received: from localhost (localhost [127.0.0.1]) (uid 1000) by filer with local; Thu, 15 Dec 2005 21:20:25 -0800 id 18325A61.43A24E99.00001038 Date: Thu, 15 Dec 2005 21:20:25 -0800 From: Kevin Brown To: pgsql-performance@postgresql.org Subject: Re: Overriding the optimizer Message-ID: <20051216052025.GB691@filer> Mail-Followup-To: Kevin Brown , pgsql-performance@postgresql.org References: <200512141603.52583.blargity@gmail.com> <7484.1134600423@sss.pgh.pa.us> <1134629567.14248.27.camel@firebolt> <200512150148.16125.blargity@gmail.com> <1134644526.14248.60.camel@firebolt> <43A1C40D.8040006@paradise.net.nz> <43A1F6DB.3080805@modgraph-usa.com> <43A226E7.7040508@paradise.net.nz> <43A22BE3.6020103@modgraph-usa.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline In-Reply-To: <43A22BE3.6020103@modgraph-usa.com> Organization: Frobozzco International User-Agent: Mutt/1.5.11 X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, score=0 required=5 tests=[none] X-Spam-Score: 0 X-Spam-Level: X-Archive-Number: 200512/386 X-Sequence-Number: 16207 Craig A. James wrote: > Hints are dangerous, and I consider them a last resort. If you consider them a last resort, then why do you consider them to be a better alternative than a workaround such as turning off enable_seqscan, when all the other tradeoffs are considered? If your argument is that planner hints would give you finer grained control, then the question is whether you'd rather the developers spend their time implementing planner hints or improving the planner. I'd rather they did the latter, as long as workarounds are available when needed. A workaround will probably give the user greater incentive to report the problem than use of planner hints. -- Kevin Brown kevin@sysexperts.com