Re: Hash aggregates blowing out memory

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Mike Harding <mvh(at)ix(dot)netcom(dot)com>
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: Hash aggregates blowing out memory
Date: 2005-02-25 22:08:22
Message-ID: 13801.1109369302@sss.pgh.pa.us
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Mike Harding <mvh(at)ix(dot)netcom(dot)com> writes:
> Any way to adjust n_distinct to be more accurate?

You could try increasing the statistics target for the relevant columns.
What does pg_stats show for the "numdistinct" estimates of the columns
you are grouping over, and does that have anything to do with reality?

regards, tom lane

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