Currently the only operator for SETs is ‘+’ which is not even strictly a union, as duplicate elements are not removed. It would be nice to have a full set (no pun intended) of operators for SETs.
e.g. UNION, INTERSECTION, SYMMETRIC DIFFERENCE, COMPLEMENT, SORT, CARTEASIAN PRODUCT, (I expect there more but my maths stopped at ‘A’ level)
At the moment to you have to convert sets to datasets to do the operations using JOIN, I would have thought a direct operator on SETS would be faster.