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From Army <qoz...@sbcglobal.net>
Subject Re: [jira] Commented: (DERBY-649) Useful indexes not used in UNION ALL
Date Wed, 21 Dec 2005 00:36:58 GMT
Daniel John Debrunner (JIRA) wrote:
> I think I've found the bug in the patch. I'd appreciate any optimizer experts
> looking at this.
> In PredicateList.pushExpressionsIntoSelect when the predicate is copied, 
> any type of binary relational node can be copied, but the new relational 
> node create is always an quality node, it is not based upon the type 
> being pushed.

[ snip code replacement ]

I'm far from an optimizer expert, but this change makes sense to me and appears 
to fulfill the "copy this predicate" notion that this block of code is dealing with.

For what that's worth,

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