Received: from maia.hub.org (maia-5.hub.org [200.46.204.29]) by mail.postgresql.org (Postfix) with ESMTP id 56259B5DC45 for ; Wed, 21 Sep 2011 00:43:51 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.29]) (amavisd-maia, port 10024) with ESMTP id 49543-08 for ; Wed, 21 Sep 2011 03:43:45 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0-rc2 Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by mail.postgresql.org (Postfix) with ESMTP id F0FCEB5DC42 for ; Wed, 21 Sep 2011 00:43:44 -0300 (ADT) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.14.2/8.14.2) with ESMTP id p8L3hc3b013064; Tue, 20 Sep 2011 23:43:38 -0400 (EDT) To: Stephen Frost cc: Andy Lester , Craig Ringer , Royce Ausburn , pgsql-performance Subject: Re: Prepared statements and suboptimal plans In-reply-to: <20110921023830.GW12765@tamriel.snowman.net> References: <4E792417.5080205@ringerc.id.au> <9289.1316565395@sss.pgh.pa.us> <7B0A863F-F304-4057-807B-9B2E6137E107@petdance.com> <10687.1316566832@sss.pgh.pa.us> <20110921023830.GW12765@tamriel.snowman.net> Comments: In-reply-to Stephen Frost message dated "Tue, 20 Sep 2011 22:38:30 -0400" Date: Tue, 20 Sep 2011 23:43:38 -0400 Message-ID: <13063.1316576618@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-2.404 tagged_above=-10 required=5 tests=BAYES_00=-1.9, RP_MATCHES_RCVD=-0.504 X-Spam-Level: X-Archive-Number: 201109/302 X-Sequence-Number: 45078 Stephen Frost writes: > * Tom Lane (tgl@sss.pgh.pa.us) wrote: >> really pretty simple: decide whether to use a custom (parameter-aware) >> plan or a generic (not-parameter-aware) plan. > Before I go digging into this, I was wondering, is this going to address > our current problem of not being able to use prepared queries and > constraint exclusion..? Possibly ... you didn't say exactly what your problem consists of. regards, tom lane