Message-ID: <490A5DCB.9060403@frostconsultingllc.com>
Date: Thu, 30 Oct 2008 18:22:19 -0700
From: Jeff Frost <jeff@frostconsultingllc.com>
Organization: Frost Consulting, LLC
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To: Tom Lane <tgl@sss.pgh.pa.us>
CC: pgsql-performance@postgresql.org
Subject: Re: Index usage problem on 8.3.3
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Tom Lane wrote:
> Okay.  What that means is that the indexes were created on data that had
> already been inserted and updated to some extent, resulting in
> HOT-update chains that turned out to be illegal for the new indexes.
> The way we deal with this is to mark the indexes as not usable by any
> query that can still see the dead HOT-updated tuples.
>
> Your best bet for dodging the problem is probably to break the operation
> into two transactions, if that's possible.  INSERT and UPDATE in the
> first xact, create the indexes at the start of the second.  (Hmm ...
> I'm not sure if that's sufficient if there are other concurrent
> transactions; but it's certainly necessary.)  Another possibility is
> to create the indexes just after data load, before you start updating
> the columns they're on.
>
> 	
Thanks Tom!

Any idea why I don't see it on 8.3.4?

-- 
Jeff Frost, Owner 	<jeff@frostconsultingllc.com>
Frost Consulting, LLC 	http://www.frostconsultingllc.com/
Phone: 916-647-6411	FAX: 916-405-4032