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

2007/5/18, Jonah H. Harris <jonah.harris@gmail.com>:
> 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