Re: wCTE behaviour

On Sat, Nov 13, 2010 at 05:23:34PM +0200, Marko Tiikkaja wrote:
> On 2010-11-13 5:08 PM +0200, Tom Lane wrote:
> >Marko Tiikkaja<marko.tiikkaja@cs.helsinki.fi>  writes:
> >>On 13 Nov 2010, at 15:41, David Fetter<david@fetter.org>  wrote:
> >>>Similarly, if a normal CTE called a data-changing function but
> >>>was nevertheless not referred to, it would still run.
> >
> >>Actually, it wouldn't.
> >
> >Indeed, and that was considered a feature when we did it.  I think
> >that having wCTEs behave arbitrarily differently on this point
> >might be a bad idea.
> 
> So these queries would behave differently?
> 
> WITH t AS (DELETE FROM foo RETURNING *) SELECT 1 WHERE false;
> 
> WITH t AS (DELETE FROM foo RETURNING *) SELECT 1 FROM t LIMIT 0;

No.

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