Received: from localhost (unknown [200.46.204.183]) by developer.postgresql.org (Postfix) with ESMTP id 89D792E003A for ; Fri, 6 Jun 2008 23:00:56 -0300 (ADT) Received: from developer.postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 97342-09 for ; Fri, 6 Jun 2008 23:00:48 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by developer.postgresql.org (Postfix) with ESMTP id C68382E0030 for ; Fri, 6 Jun 2008 23:00:53 -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 m5720glW009607; Fri, 6 Jun 2008 22:00:42 -0400 (EDT) To: "Joshua D. Drake" cc: Robert Treat , pgsql-hackers@postgresql.org, Peter Eisentraut , Greg Smith , Andreas Pflug , Decibel! , Josh Berkus Subject: Re: Overhauling GUCS In-reply-to: <1212800891.14299.35.camel@jd-laptop> References: <48409D1E.3070208@agliodbs.com> <29525.1212613052@sss.pgh.pa.us> <200806061435.01196.peter_e@gmx.net> <200806061624.29105.xzilla@users.sourceforge.net> <8358.1212797962@sss.pgh.pa.us> <1212800891.14299.35.camel@jd-laptop> Comments: In-reply-to "Joshua D. Drake" message dated "Fri, 06 Jun 2008 18:08:11 -0700" Date: Fri, 06 Jun 2008 22:00:41 -0400 Message-ID: <9606.1212804041@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200806/338 X-Sequence-Number: 119451 "Joshua D. Drake" writes: > Not surprising really. It is a simple adjustment to make and it also is > easy to spot when its a problem. However it is not trivial to test for > (in terms of time and effort). I know 10 is wrong and so do you. Sure. But what is right? I'm afraid to just push it to (say) 100 because of the possibility of O(N^2) behavior in eqjoinsel. Somebody needs to do some measurements on somewhat realistic scenarios. regards, tom lane