Re: [PERFORM] Posible planner improvement?

A Dimecres 21 Maig 2008, Richard Huxton va escriure:
> Luke Lonergan wrote:
> > The problem is that the implied join predicate is not being
> > propagated. This is definitely a planner deficiency.
>
> IIRC only equality conditions are propagated and gt, lt, between aren't.
> I seem to remember that the argument given was that the cost of
> checking for the ability to propagate was too high for the frequency
> when it ocurred.
>
> Of course, what was true for code and machines of 5 years ago might not
> be so today.

Hope this can be revisited given the huge difference in this case: 80 minutes
to 1 second.

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Albert Cervera Areny
Dept. Informàtica Sedifa, S.L.

Av. Can Bordoll, 149
08202 - Sabadell (Barcelona)
Tel. 93 715 51 11
Fax. 93 715 51 12

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