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Re: select count(*) from a large table is very slow - Mailing list pgsql-admin

From Daniel Cristian Cruz
Subject Re: select count(*) from a large table is very slow
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In response to Re: select count(*) from a large table is very slow  ("Jonah H. Harris" <[email protected]>)
Responses Re: select count(*) from a large table is very slow
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2007/5/18, Jonah H. Harris <[email protected]>:
> 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.

Oops... INSERT or DELETE... :)

And remember that if using TRUNCATE, it will not run your trigger and
you will need to reset the counter manually.

Regards...
--
Daniel Cristian Cruz

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