Re: Postgresql 8.3 statistic stadistinct value dead wrong even with default_statistics_target=1000

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Maxim Boguk <mboguk(at)masterhost(dot)ru>
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: Postgresql 8.3 statistic stadistinct value dead wrong even with default_statistics_target=1000
Date: 2008-08-22 15:37:35
Message-ID: 13326.1219419455@sss.pgh.pa.us
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Maxim Boguk <mboguk(at)masterhost(dot)ru> writes:
> [ ndistinct estimates way off ]

Estimating the number of distinct values in a distribution with a long
tail is just a really hard problem :-(

regards, tom lane

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