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Date: Thu, 29 Nov 2007 21:30:24 +0100
From: "Steinar H. Gunderson" <sgunderson@bigfoot.com>
To: pgsql-performance@postgresql.org
Subject: Re: GiST indexing tuples
Message-ID: <20071129203024.GB5705@uio.no>
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On Thu, Nov 29, 2007 at 03:23:10PM -0500, Matthew T. O'Connor wrote:
> Sorry in advance if this is a stupid question, but how is this better than 
> two index, one on "a" and one on "b"?  I supposed there could be a space 
> savings but beyond that?

You could index on both columns simultaneously without a bitmap index scan.

/* Steinar */
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