Re: Why pgAdmin III guru suggests VACUUM in 8.1 - Mailing list pgsql-general

From Jim C. Nasby
Subject Re: Why pgAdmin III guru suggests VACUUM in 8.1
Date
Msg-id 20051122191251.GW19279@pervasive.com
Whole thread Raw
In response to Re: Why pgAdmin III guru suggests VACUUM in 8.1  ("Andrus" <eetasoft@online.ee>)
List pgsql-general
On Tue, Nov 22, 2005 at 09:01:25PM +0200, Andrus wrote:
> Jim,
>
> > Keep in mind that if analyze has never been run on a table the database
> > will assume 1000 rows, which is definately off from 122 rows.
>
> autovacuum processes this tabele regularly.
> I believed that autovacuum can update the row count to be real.

It can, but without looking at logs of what autovacuum has actually done
there's no way to know if it actually has analyzed that table or not.

> > You might want to ask on the pgAdmin list. Though I'd recommend against
> > calling the guru 'stupid' over there. :)
>
> I'm creating application which upsizes existing data to new postgres 8.1
> database.
>
> Will I need to run VACUUM ANALYZE after upsizing ?

Upsizes? Are you adding more data? If so then yes, analyze would be
good, though autovacuum should handle it for you.

> Must I enable statitics collection for this database ?

Well, autovacuum depends on it; see
http://www.postgresql.org/docs/8.1/interactive/maintenance.html#AUTOVACUUM
--
Jim C. Nasby, Sr. Engineering Consultant      jnasby@pervasive.com
Pervasive Software      http://pervasive.com    work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf       cell: 512-569-9461

pgsql-general by date:

Previous
From: "Andrus"
Date:
Subject: Re: Why pgAdmin III guru suggests VACUUM in 8.1
Next
From: "Andrus"
Date:
Subject: Re: Why pgAdmin III guru suggests VACUUM in 8.1