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Re: Premature view materialization in 8.2?

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: "Jonathan Ellis" <jonathan(at)utahpython(dot)org>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: Premature view materialization in 8.2?
Date: 2007-04-06 17:40:27
Message-ID: 15092.1175881227@sss.pgh.pa.us (view raw or flat)
Thread:
Lists: pgsql-performance
"Jonathan Ellis" <jonathan(at)utahpython(dot)org> writes:
> On 4/6/07, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> Yeah, it sure is the same plan, and 8.2 seems to be a tad faster right
>> up to the hash join on user_id.  Is user_id a textual datatype?

> user_id is an int; they are both C locale.

Really!?  So much for that theory.

Is work_mem set similarly on both installations?

The only other thing I can think is that you've exposed some unfortunate
corner case in the hash join logic.  Would you be willing to send me
(off-list) the lists of user_ids being joined?  That would be the
clan_members.user_id column and the user_id column from the join of
parties and clan_participants.

			regards, tom lane

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Subject: Re: Premature view materialization in 8.2?
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