Re: simple question

Is this correct?

vacuum by itself just cleans out the old extraneous tuples so that they
aren't in the way anymore
vacuum analyze rebuilds indexes. If you add an index to a table it won't be
used until you vacuum analyze it
vacuum full actually compresses the table on disk by reclaiming the space
from the old tuples after they have been removed.

----- Original Message -----
From: "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: "Paulo Jan" <admin(at)digital(dot)ddnet(dot)es>
Cc: <pgsql-general(at)postgresql(dot)org>
Sent: Wednesday, November 12, 2003 8:38 AM
Subject: Re: [GENERAL] Perfomance difference between 7.2 and 7.3

> Paulo Jan <admin(at)digital(dot)ddnet(dot)es> writes:
> > -> Seq Scan on todocinetv (cost=0.00..37768.90 rows=28792
> > width=8)
>
> The estimated cost seems to be more than one disk page read per row
> returned. This suggests to me that you have a huge amount of dead space
> in that table --- try a VACUUM FULL on it. If that fixes the problem,
> then you need to improve your housekeeping procedures on the 7.2
> installation: run vacuums more often and ensure that your FSM settings
> are large enough.
>
> regards, tom lane
>
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