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Message-ID: <44AE1C07.60009@logix-tt.com>
Date: Fri, 07 Jul 2006 10:32:07 +0200
From: Markus Schaber <schabi@logix-tt.com>
Organization: Logical Tracking and Tracing International AG, Switzerland
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To: "Craig A. James" <cjames@modgraph-usa.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: need vacuum after insert/truncate/insert?
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	<44ADBDB8.5010008@modgraph-usa.com>
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Hi, Craig,

Craig A. James wrote:
> If I insert a bunch of rows, then truncate, then insert a bunch more
> rows, do I need to vacuum?  I've been assuming that TRUNCATE TABLE is a
> brute-force technique that more-or-less tosses the old table and starts
> fresh so that no vacuum is necessary.
> 
> Second question: Same scenario as above, but now the table has indexes. 
> Is a reindex needed, or are the indexes they "truncated" too?

AFAIK, both table and indices are "cut down" nicely.

But you will need an ANALYZE after refilling of the table, to have
current statistics.


HTH,
Markus


-- 
Markus Schaber | Logical Tracking&Tracing International AG
Dipl. Inf.     | Software Development GIS

Fight against software patents in EU! www.ffii.org www.nosoftwarepatents.org