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Message-ID: <4FFE2704.7020106@ringerc.id.au>
Date: Thu, 12 Jul 2012 09:23:16 +0800
From: Craig Ringer <ringerc@ringerc.id.au>
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To: Matthew Woodcraft <matthew@woodcraft.me.uk>
CC: pgsql-performance@postgresql.org
Subject: Re: DELETE vs TRUNCATE explanation
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On 07/12/2012 02:10 AM, Matthew Woodcraft wrote:
> I think a documentation change would be worthwhile. At the moment the 
> TRUNCATE page says, with no caveats, that it is faster than 
> unqualified DELETE.

+1  to updating the docs to reflect the fact that TRUNCATE may have a 
higher fixed cost than DELETE FROM table; but also prevents bloat.

It's a weird little corner case, but with database-backed unit testing 
it's going to become a more significant one whether or not it feels like 
it makes any sense.

--
Craig Ringer