RPost wrote:......Yes. I included the UNION/UNION ALL example because it is important to get the associativity right even in the UNION case. I have updated my paper (attached) to say so explicitly, and include an example with UNION and EXCEPT.
Anyway, I think you meant to compare UNION (or UNION ALL) and INTERSECT here (as you did EXCEPT/INTERSECT below this) to illustrate the higher precedence of INTERSECT.
It's now here: http://incubator.apache.org/derby/papers/Intersect-design.html
-jean
