Why does the order of the SELECT statements in the UNION affect the result?This first SQL produces the result I want.SELECT cat_id AS catid, manufacturer AS mfr, model, a_class_id as class_id FROM ...

I need to form the equivalent of a Union Join in Oracle 8i, even though a Union Join doesn't appear to be supported in 8i. I might be able to manipulate a Full Outer Join to get the results I need ...

This paper proposes a method SQL detection and algorithm to detect and prevent the tautology and union query based attacks at run time.