Patrick Welche <prlw1(at)newn(dot)cam(dot)ac(dot)uk> writes:
> I think this is right..
I think not. The section in question is defining the mathematical
terms of set theory, not their representation in SQL.
(BTW, is this file even still used? Right offhand I can't see it
anywhere in the 7.2 documentation set.)
regards, tom lane