X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 9402452825 for ; Wed, 22 Jun 2005 13:17:34 -0300 (ADT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 57053-06 for ; Wed, 22 Jun 2005 16:17:25 +0000 (GMT) Received: from gwmta.wicourts.gov (gwmta.wicourts.gov [165.219.244.91]) by svr1.postgresql.org (Postfix) with ESMTP id C8484528C7 for ; Wed, 22 Jun 2005 13:17:23 -0300 (ADT) Received: from Courts-MTA by gwmta.wicourts.gov with Novell_GroupWise; Wed, 22 Jun 2005 11:16:04 -0500 Message-Id: X-Mailer: Novell GroupWise Internet Agent 6.5.2 Date: Tue, 21 Jun 2005 16:11:40 -0500 From: "Kevin Grittner" To: , Cc: , Subject: Re: Limit clause not using index Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Disposition: inline X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.022 tagged_above=0 required=5 tests=AWL X-Spam-Level: X-Archive-Number: 200506/438 X-Sequence-Number: 13075 I just tried this on 8.0.3. A query which runs very fast through an index on a 25 million row table blocked when I dropped the index within a database transaction. As soon as I rolled back the database transactiton, the query completed, the index appears fine, and the query runs fast, as usual. So, it looks like this is right except for the assertion that the index is still available for other queries. -Kevin >>> Tobias Brox 06/21/05 2:46 PM >>> [John A Meinel - Tue at 10:14:24AM -0500] > I believe if you drop the indexes inside a transaction, they will still > be there for other queries, and if you rollback instead of commit, you > won't lose anything. Has anyone tested this? (sorry, I only have the production database to play with at the moment, and I don't think I should play with it ;-) -- Tobias Brox, Beijing ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to majordomo@postgresql.org so that your message can get through to the mailing list cleanly