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From: Tom Lane <tgl@sss.pgh.pa.us>
To: David Conlin <dc345@cantab.net>
cc: pgsql-performance@lists.postgresql.org
Subject: Re: Change in CTE treatment in query plans?
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Comments: In-reply-to David Conlin <dc345@cantab.net>
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David Conlin <dc345@cantab.net> writes:
> Does anyone know if there's been a change in the way values for CTEs are 
> displayed in query plans?

Offhand I don't recall any such changes, nor does a cursory look
through explain.c find anything promising.

If you're concerned with a multiply-referenced CTE, one possibility
for funny results is that the blame for its execution cost could be
spread across the multiple call sites.  The same can happen with
initplans/subplans.  But I'm just guessing; you didn't show any
concrete examples so it's hard to be definite.

			regards, tom lane