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WHERE clause processing
Posted by: Maxx Kazimieszko
Date: November 15, 2005 05:20PM


Does anyone know - as I can't seem to find it in documentation - how the multiple expressions in WHERE clause are processed?

I mean, if WHERE clause contains the following:
field1=val1 AND field2=val2
are both parts of the conjunction processed?
If for given row first expression (field1=val1) is FALSE, there is no need to process the other one
- the whole row can be immediately excluded from the results set, isn't it so?
This would be particularly useful if results of two subqueries were to be calculated...

Kind regards,

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Written By
WHERE clause processing
November 15, 2005 05:20PM
November 15, 2005 07:32PM

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