Simetrical wrote:
Not as important as intersections, no. But while
I've been bitten for
spouting off about stuff I'm ignorant of before, surely calculating a
union would be cheaper than calculating an intersection anyway?
I don't think so. Basically, the way you do a union is make a list
including all the articles in both categories (including duplicates).
Then, you remove...the intersection.
Matthew Flaschen