Re: select count(*) from a large table is very slow

On 5/18/07, Kenneth Marshall <ktm@rice.edu> wrote:
> Make a summary table and select from there instead.

Yes, a summary table updated by triggers is the only way to have
correct numbers... but you also pay the overhead of maintaining those
numbers on every INSERT/UPDATE statement.  If you just need
*reasonable* guesstimates, use reltuples in pg_class after an analyze.

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Jonah H. Harris, Software Architect | phone: 732.331.1324
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