Re: Rewrite, normal execution vs. EXPLAIN ANALYZE - Mailing list pgsql-hackers

From David Fetter
Subject Re: Rewrite, normal execution vs. EXPLAIN ANALYZE
Date
Msg-id 20100723175239.GB26130@fetter.org
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In response to Rewrite, normal execution vs. EXPLAIN ANALYZE  (Marko Tiikkaja <marko.tiikkaja@cs.helsinki.fi>)
Responses Re: Rewrite, normal execution vs. EXPLAIN ANALYZE
List pgsql-hackers
On Thu, Jul 22, 2010 at 08:43:35PM +0300, Marko Tiikkaja wrote:
> Hi,
> 
> From the code I understood that when executing a query "normally",
> in READ COMMITTED mode, we take a new snapshot for every query that
> comes out of rewrite.  But in an EXPLAIN ANALYZE, we only update the
> CID of the snapshot taken when the EXPLAIN started.
> 
> Did I misunderstand the code?  And if I didn't, why do we do this
> differently?

You mentioned in IRC that this was in aid of getting wCTEs going.  How
are these things connected?

Cheers,
David.
-- 
David Fetter <david@fetter.org> http://fetter.org/
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