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Old 04-12-2008, 06:58 AM
Jim C. Nasby
 
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Default Re: Vacuum, analyze, and setting reltuples of pg_class

On Mon, Dec 11, 2006 at 12:08:30PM -0500, Tom Lane wrote:
> "Greg Sabino Mullane" <greg@turnstep.com> writes:
> > Short version: is it optimal for vacuum to always populate reltuples
> > with live rows + dead rows?

>
> If we didn't do that, it would tend to encourage the use of seqscans on
> tables with lots of dead rows, which is probably a bad thing.


So then why does vacuum do that? ISTM that it makes more sense for it to
act the same as analyze and only count live rows.
--
Jim Nasby jim@nasby.net
EnterpriseDB http://enterprisedb.com 512.569.9461 (cell)

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