Re: Rewrite, normal execution vs. EXPLAIN ANALYZE

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От David Fetter
Тема Re: Rewrite, normal execution vs. EXPLAIN ANALYZE
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Msg-id 20100723175239.GB26130@fetter.org
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Ответ на Rewrite, normal execution vs. EXPLAIN ANALYZE  (Marko Tiikkaja <marko.tiikkaja@cs.helsinki.fi>)
Ответы Re: Rewrite, normal execution vs. EXPLAIN ANALYZE  (Marko Tiikkaja <marko.tiikkaja@cs.helsinki.fi>)
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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.
-- 
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