Re: Impact of foreign keys on a simple count(*) ?

From: "C(dot) Bensend" <benny(at)bennyvision(dot)com>
To: pgsql-sql(at)postgresql(dot)org
Subject: Re: Impact of foreign keys on a simple count(*) ?
Date: 2004-10-09 04:13:02
Message-ID: 50512.63.227.74.41.1097295204.squirrel@63.227.74.41
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> Foreign keys have zero, nada, zilch to do with the performance of
> count(*).

OK, I just wanted to make sure.

> The only plausible theory I can think of for the performance
> difference is that in your "new" database the table has been through
> several mass updates, leading to a whole lot of dead rows and a much
> larger physical table size to scan through. I'd suggest a VACUUM
> VERBOSE on both old and new copies of the table to get an idea of the
> relative physical sizes. You might need a VACUUM FULL to get the new
> table back down to a reasonable size...

Oh good lord.

*waves the Idiot Flag as he slinks back under his rock*

Thank you, Tom, for your patience. That was it. I'm a potatohead,
but I'm learning. :)

Benny, swearing he DID do a vacuum, but obviously not...

--
"Even if a man chops off your hand with a sword, you still have two nice,
sharp bones to stick in his eyes."
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