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 C53655288B for ; Wed, 22 Jun 2005 00:55:25 -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 01143-04 for ; Wed, 22 Jun 2005 03:55:16 +0000 (GMT) Received: from exobox.exoweb.net (unknown [221.122.43.98]) by svr1.postgresql.org (Postfix) with SMTP id D4EFC5293C for ; Wed, 22 Jun 2005 00:55:07 -0300 (ADT) Received: (qmail 15323 invoked from network); 22 Jun 2005 03:54:56 -0000 Received: from exo185.exoweb.net (HELO tobias.nordicbet.invalid) (192.168.0.185) by 0 with SMTP; 22 Jun 2005 03:54:56 -0000 Received: by tobias.nordicbet.invalid (Postfix, from userid 500) id 69DB4E0CE0; Wed, 22 Jun 2005 11:54:56 +0800 (CST) Date: Wed, 22 Jun 2005 11:54:55 +0800 From: Tobias Brox To: Tom Lane Cc: Tobias Brox , John A Meinel , Yves Vindevogel , pgsql-performance@postgresql.org Subject: Re: Limit clause not using index Message-ID: <20050622035455.GP7839@tobias> References: <42B8275C.8040300@arbash-meinel.com> <7e514564b9a159480857de53cc1764fd@implements.be> <42B82ED0.1010009@arbash-meinel.com> <20050621194639.GG22746@oppetid.no> <17468.1119388807@sss.pgh.pa.us> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <17468.1119388807@sss.pgh.pa.us> Organization: Group Nordicbet User-Agent: Mutt/1.5.6i X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0 tagged_above=0 required=5 tests= X-Spam-Level: X-Archive-Number: 200506/421 X-Sequence-Number: 13058 [Tom Lane - Tue at 05:20:07PM -0400] > > Certainly. Bear in mind though that DROP INDEX will acquire exclusive > lock on the index's table, so until you roll back, no other transaction > will be able to touch the table at all. So the whole thing may be a > nonstarter in a production database anyway :-(. That's what I was afraid of. I was running psql at the production DB without starting a transaction (bad habit, I know) and tried to drop an index there, but I had to cancel the transaction, it took forever and in the same time blocking all the revenue-generating activity. -- Tobias Brox, +86-13521622905 Nordicbet, IT dept