Received: from localhost (unknown [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id EEB1E2E0066 for ; Thu, 6 Dec 2007 15:50:40 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 78686-09 for ; Thu, 6 Dec 2007 15:50:38 -0400 (AST) Received: from vms046pub.verizon.net (vms046pub.verizon.net [206.46.252.46]) by postgresql.org (Postfix) with ESMTP id 400FD2E2D72 for ; Thu, 6 Dec 2007 15:50:38 -0400 (AST) Received: from osgiliath.mathom.us ([71.178.10.55]) by vms046.mailsrvcs.net (Sun Java System Messaging Server 6.2-6.01 (built Apr 3 2006)) with ESMTPA id <0JSN00DE58GDPG8F@vms046.mailsrvcs.net> for pgsql-performance@postgresql.org; Thu, 06 Dec 2007 13:50:37 -0600 (CST) Received: from localhost (localhost [127.0.0.1]) by osgiliath.mathom.us (Postfix) with ESMTP id 005D71F816 for ; Thu, 06 Dec 2007 14:50:35 -0500 (EST) Received: from osgiliath.mathom.us ([127.0.0.1]) by localhost (osgiliath.home.mathom.us [127.0.0.1]) (amavisd-new, port 10024) with LMTP id LI3gyNOeAN6B for ; Thu, 06 Dec 2007 14:50:34 -0500 (EST) Received: by osgiliath.mathom.us (Postfix, from userid 1000) id 6091A1F80D; Thu, 06 Dec 2007 14:50:34 -0500 (EST) Date: Thu, 06 Dec 2007 14:50:33 -0500 From: Michael Stone Subject: Re: TB-sized databases In-reply-to: <15753.1196957598@sss.pgh.pa.us> To: pgsql-performance@postgresql.org Mail-followup-to: pgsql-performance@postgresql.org Message-id: <20071206195030.GQ5294@mathom.us> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii; format=flowed Content-disposition: inline X-Virus-Scanned: Debian amavisd-new at mathom.us X-Pgp-Fingerprint: 53 FF 38 00 E7 DD 0A 9C 84 52 84 C5 EE DF 7C 88 References: <4544e0330711260904g45d893a8ub1731e245aa8fc84@mail.gmail.com> <13851.1196351131@sss.pgh.pa.us> <1196352866.4246.1304.camel@ebony.site> <200712051507.22745.xzilla@users.sourceforge.net> <1196933896.4255.340.camel@ebony.site> <20071206154212.GP5294@mathom.us> <15753.1196957598@sss.pgh.pa.us> User-Agent: Mutt/1.5.13 (2006-08-11) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200712/86 X-Sequence-Number: 27902 On Thu, Dec 06, 2007 at 11:13:18AM -0500, Tom Lane wrote: >Indeed, and if you've got examples where it's that far off, you should >report them. Yeah, the trick is to get it to a digestable test case. The basic scenario (there are more tables & columns in the actual case) is a set of tables partitioned by date with a number of columns in one table referencing rows in the others: Table A (~5bn rows / 100's of partitions) time Bkey1 Ckey1 Bkey2 Ckey2 Table B (~1bn rows / 100's of partitions) Bkey Bval Table C (~.5bn rows / 100's of partitions) Ckey Cval Bkey and Ckey are unique, but the planner doesn't know that. Mike Stone