From: C. Bensend <benny@bennyvision.com>
To: pgsql-sql@postgresql.org
Subject: Re: Impact of foreign keys on a simple count(*) ?
Date: Fri, 8 Oct 2004 23:13:02 -0500 (CDT)
Message-ID: <50512.63.227.74.41.1097295204.squirrel@63.227.74.41> (raw)
In-Reply-To: <23596.1097293763@sss.pgh.pa.us>
References: <51319.63.227.74.41.1097293075.squirrel@63.227.74.41>
<23596.1097293763@sss.pgh.pa.us>
> 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."
-- .sig on Slashdot
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To: pgsql-sql@postgresql.org
Cc: benny@bennyvision.com
Subject: Re: Impact of foreign keys on a simple count(*) ?
In-Reply-To: <50512.63.227.74.41.1097295204.squirrel@63.227.74.41>
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