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
Views: Raw Message | Whole Thread | Download mbox | Resend email
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

In response to

Responses

Browse pgsql-performance by date

  From Date Subject
Next Message Jonathan Ellis 2007-04-06 17:57:27 Re: Premature view materialization in 8.2?
Previous Message Geoffrey 2007-04-06 17:04:53 Re: more on high load on postgres 7.4.16