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Re: Hash aggregates blowing out memory - Mailing list pgsql-general

From Tom Lane
Subject Re: Hash aggregates blowing out memory
Date
Msg-id 13801.1109369302@sss.pgh.pa.us
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In response to Re: Hash aggregates blowing out memory  (Mike Harding <mvh@ix.netcom.com>)
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Mike Harding <mvh@ix.netcom.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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