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	Fri, 07 Jul 2006 16:15:27 PDT
Date: Fri, 7 Jul 2006 16:15:27 -0700 (PDT)
From: Richard Broersma Jr <rabroersma@yahoo.com>
Subject: Re: VACUUM vs. REINDEX
To: William Scott Jordan <wsjordan@brownpapertickets.com>,
	pgsql-performance@postgresql.org
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> I'm trying to decide now if we need to include a daily REINDEX along 
> with our daily VACUUM FULL, and more importantly I'm just curious to 
> know why we should or shouldn't do that.
> 
> Any information on this subject would be appreciated.

My understanding is that vaccum full frees all of the unused space from deprecated tuples in the
table.  This effective reduces that amount of tuples that will be sequencially scanned which
deceases sequencial scan times.

reindex rebuilds the index to removed all of the deprecated tuple references.  This free memory
and reduces that time it takes to scan the index.

Thats how I understand it.

Regards,

Richard Broersma Jr.