Received: from maia.hub.org (maia-2.hub.org [200.46.204.251]) by mail.postgresql.org (Postfix) with ESMTP id A4EA3ED8E0A for ; Mon, 14 Nov 2011 04:58:23 -0400 (AST) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.251]) (amavisd-maia, port 10024) with ESMTP id 90709-02 for ; Mon, 14 Nov 2011 08:58:17 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0-rc2 Received: from mail.archonet.com (84-51-143-99.archon037.adsl.metronet.co.uk [84.51.143.99]) by mail.postgresql.org (Postfix) with ESMTP id 4A7F4ED8E09 for ; Mon, 14 Nov 2011 04:58:16 -0400 (AST) Received: from [192.168.1.36] (dell36.office.archonet.com [192.168.1.36]) by mail.archonet.com (Postfix) with ESMTP id 32EBA7C029; Mon, 14 Nov 2011 08:58:15 +0000 (GMT) Message-ID: <4EC0D827.8090601@archonet.com> Date: Mon, 14 Nov 2011 08:58:15 +0000 From: Richard Huxton User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.23) Gecko/20110921 Lightning/1.0b2 Thunderbird/3.1.15 MIME-Version: 1.0 To: Sergey Konoplev CC: Stephen Frost , Anibal David Acosta , pgsql-performance@postgresql.org Subject: Re: unlogged tables References: <005501cca0ad$b9478440$2bd68cc0$@devshock.com> <20111111201822.GN24234@tamriel.snowman.net> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-0.918 tagged_above=-10 required=5 tests=BAYES_00=-1.9, RDNS_DYNAMIC=0.982 X-Spam-Level: X-Archive-Number: 201111/157 X-Sequence-Number: 45668 On 14/11/11 08:10, Sergey Konoplev wrote: > Hi, > > On 12 November 2011 00:18, Stephen Frost wrote: >> In a crash, unlogged tables are automatically truncated. > > BTW I wonder what for they are truncated in a crash case? Because they bypass the transaction-log (WAL), hence unlogged. There's no way to know whether there were partial updates applied when the system restarts. -- Richard Huxton Archonet Ltd