Re: Performance penalty when using WITH

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Li Jin <ljin(at)tripadvisor(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: Performance penalty when using WITH
Date: 2011-07-29 17:40:27
Message-ID: 28960.1311961227@sss.pgh.pa.us
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Li Jin <ljin(at)tripadvisor(dot)com> writes:
> Anyone knows why the planner is doing this?

WITH is an optimization fence. This is intentional and documented.

regards, tom lane

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