Re: statistics horribly broken for row-wise comparison

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Merlin Moncure <mmoncure(at)gmail(dot)com>
Cc: PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: statistics horribly broken for row-wise comparison
Date: 2009-03-03 01:29:16
Message-ID: 1692.1236043756@sss.pgh.pa.us
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Merlin Moncure <mmoncure(at)gmail(dot)com> writes:
> It looks like for row-wise comparison, only the first column is used
> for generating the expected row count.

[ shrug... ] Short of multi-column statistics, it's hard to see how to
do better.

regards, tom lane

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