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

"C. Bensend" <benny@bennyvision.com> writes:
>    Is it the addition of the multiple foreign keys that is slowing this
> down so much?

Foreign keys have zero, nada, zilch to do with the performance of
count(*).  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...
        regards, tom lane