> >>I found I'm suffering from an effect detailed in a previous thread titled > >> > >> Does "correlation" mislead the optimizer on large tables? > > > > > >I don't know about large tables, but this is a big problem and > >something I'm going to spend some time validating later today. I > >think Manfred's patch is pretty good and certainly better than where > >we are but I haven't used it yet to see if it's the magic ticket for > >many of these index problems. > > I had to dig through a lot of archives to find this. Is this the patch, > from last October? > > http://members.aon.at/pivot/pg/16-correlation.diff > > If so, I'll try it out and report my results.
Same guy, but that patch is pretty out of date and has been replaced by some newer work that's much better. From: Manfred Koizar <[EMAIL PROTECTED]> Cc: [EMAIL PROTECTED] Subject: Re: [HACKERS] Correlation in cost_index() Date: Wed, 20 Aug 2003 19:57:12 +0200 Message-ID: <[EMAIL PROTECTED]> and From: Manfred Koizar <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] Subject: [HACKERS] Again on index correlation Date: Wed, 20 Aug 2003 21:21:14 +0200 Message-ID: <[EMAIL PROTECTED]> -sc -- Sean Chittenden ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html