Received: from localhost (maia-2.hub.org [200.46.204.187]) by postgresql.org (Postfix) with ESMTP id 356B89FB582 for ; Wed, 18 Apr 2007 07:47:33 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.187]) (amavisd-maia, port 10024) with ESMTP id 00475-08 for ; Wed, 18 Apr 2007 07:47:26 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.4 Received: from mail.metronet.co.uk (mail.metronet.co.uk [213.162.97.75]) by postgresql.org (Postfix) with ESMTP id 396C29FB51F for ; Wed, 18 Apr 2007 07:47:30 -0300 (ADT) Received: from server3.office.archonet.com (84-51-143-99.archon037.adsl.metronet.co.uk [84.51.143.99]) by smtp.metronet.co.uk (MetroNet Mail) with ESMTP id 8DB7374E8D; Wed, 18 Apr 2007 11:47:28 +0100 (BST) Received: from [192.168.1.36] (dell36.office.archonet.com [192.168.1.36]) by server3.office.archonet.com (Postfix) with ESMTP id 412332740EE; Wed, 18 Apr 2007 10:22:36 +0100 (BST) Message-ID: <4625E35C.2060708@archonet.com> Date: Wed, 18 Apr 2007 10:22:36 +0100 From: Richard Huxton User-Agent: IceDove 1.5.0.9 (X11/20061220) MIME-Version: 1.0 To: "Craig A. James" Cc: pgsql-performance@postgresql.org Subject: Re: Basic Q on superfluous primary keys References: <20070414075947.e5fbeec8.wmoran@collaborativefusion.com> <46239000.7000708@modgraph-usa.com> <46259937.7030502@modgraph-usa.com> In-Reply-To: <46259937.7030502@modgraph-usa.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200704/328 X-Sequence-Number: 24205 Craig A. James wrote: > Since we're only aggregating information, we have > no control over the data that these companies provide. And at the end of the day that's the root of the problem. It's easy to be lulled into "well it looks like a primary key" rather than being able to guarantee it. -- Richard Huxton Archonet Ltd