Date: Fri, 8 Jun 2007 10:20:30 -0400
From: Andrew Sullivan <ajs@crankycanuck.ca>
To: pgsql-admin@postgresql.org
Subject: Re: the right time to vacuum database?
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On Fri, Jun 08, 2007 at 06:29:55AM -0700, Charles.Hou wrote:
> 
> i have traced the size of the table. About 1000 new rows  will be
> inserted into the table in one day. each row has 300 bytes.
> 1000*300/1024=293K, but the size of this table had been increased 3MB.
> 3MB-293K=2.7MB...Why?where is the 2.7MB?

How do you know what the size of the table is?  You had at least two
tables you were working on before.  I think there must be something
you're not communicating completely.  (And why are you worried about
less than 3 Meg anyway?  Regular vacuum will leave some empty space
around for new data, which means you don't have to go down to the
filesystem to make the file bigger before you write it it.  This is a
Good Thing.)

Please go back and run VACUUM VERBOSE on the table you killed the
vacuum on before.

A

-- 
Andrew Sullivan  | ajs@crankycanuck.ca
However important originality may be in some fields, restraint and 
adherence to procedure emerge as the more significant virtues in a 
great many others.   --Alain de Botton