Received: from localhost (maia-5.hub.org [200.46.204.182]) by postgresql.org (Postfix) with ESMTP id C45629FB41C for ; Tue, 30 Jan 2007 16:56:17 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.182]) (amavisd-new, port 10024) with ESMTP id 38378-05 for ; Tue, 30 Jan 2007 16:56:14 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey-1.7.4 Received: from exprod6og53.obsmtp.com (exprod6og53.obsmtp.com [64.18.1.187]) by postgresql.org (Postfix) with SMTP id DD0199FA297 for ; Tue, 30 Jan 2007 16:56:16 -0400 (AST) Received: from source ([63.240.6.46]) (using TLSv1) by exprod6ob53.postini.com ([64.18.5.12]) with SMTP; Tue, 30 Jan 2007 12:56:07 PST Received: from 172.16.1.92 by mail.mi8.com with ESMTP (- Welcome to Mi8 Corporation www.Mi8.com (D2)); Tue, 30 Jan 2007 13:20:32 -0500 X-Server-Uuid: 7829E76E-BB9E-4995-8473-3C0929DF7DD1 Received: from MI8NYCMAIL08.Mi8.com ([172.16.1.164]) by d01smtp08.Mi8.com with Microsoft SMTPSVC(6.0.3790.1830); Tue, 30 Jan 2007 13:20:31 -0500 Received: from 63.80.24.130 ([63.80.24.130]) by MI8NYCMAIL08.Mi8.com ( [172.16.1.190]) via Exchange Front-End Server mi8owa.mi8.com ( [172.16.1.134]) with Microsoft Exchange Server HTTP-DAV ; Tue, 30 Jan 2007 18:20:31 +0000 User-Agent: Microsoft-Entourage/11.3.3.061214 Date: Tue, 30 Jan 2007 10:20:28 -0800 Subject: Re: Querying distinct values from a large table From: "Luke Lonergan" To: "Alvaro Herrera" , "Gregory Stark" cc: "Chad Wagner" , "Simon Riggs" , "Igor Lobanov" , "Richard Huxton" , pgsql-performance@postgresql.org Message-ID: Thread-Topic: [PERFORM] Querying distinct values from a large table Thread-Index: AcdEm1Frj8HnT7COEduYNwAWy4o9DA== In-Reply-To: <20070130170443.GJ2303@alvh.no-ip.org> MIME-Version: 1.0 X-OriginalArrivalTime: 30 Jan 2007 18:20:31.0838 (UTC) FILETIME=[53B59FE0:01C7449B] X-WSS-ID: 69A153FA4M83058480-01-01 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200701/433 X-Sequence-Number: 23034 Alvaro, On 1/30/07 9:04 AM, "Alvaro Herrera" wrote: >> (Incidentally I'm not sure where 2-5x comes from. It's entirely dependant on >> your data distribution. It's not hard to come up with distributions where >> it's >> 1000x as fast and others where there's no speed difference.) > > So the figure is really "1-1000x"? I bet this one is more impressive in > PHB terms. You got me - I'll bite - what's PHB? - Luke