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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Jon Nelson <jnelson+pgsql@jamponi.net>
Cc: pgsql-performance@postgresql.org
Subject: Re: temporary tables, indexes, and query plans
Date: Wed, 27 Oct 2010 15:43:13 -0400
Message-ID: <26190.1288208593@sss.pgh.pa.us> (raw)
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Jon Nelson <jnelson+pgsql@jamponi.net> writes:
> The most recent experiment shows me that, unless I create whatever
> indexes I would like to see used *before* the large (first) update,
> then they just don't get used. At all.

You're making a whole lot of assertions here that don't square with
usual experience.  I think there is some detail about what you're
doing that affects the outcome, but since you haven't shown a concrete
example, it's pretty hard to guess what the critical detail is.

			regards, tom lane



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