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Re: Can't understand why optimizer doesn't work properly :(
Posted by: KimSeong Loh
Date: July 24, 2007 06:02PM

It is not possible to execute the subquery first when it does not know the value of Messages.Ask

Only after you execute the outer query, you can obtain the value of Messages.Ask, then substitute it into the subquery to be executed, the subquery needs to be executed once for every row of the outer query.

Write out 2 tables with a few rows and try to execute this manually and see if you can do it or not. If not, the server cannot either.

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Re: Can't understand why optimizer doesn't work properly :(
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July 24, 2007 06:02PM


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