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

Greetings!

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,
Maxx

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