i suppose it´s been asked before (i´ve seen the question, but not the
answer, in the mailing list archives):
how do you create a set type, i.e. an attribute which is, say ´set of
char´; and then you´d want to run some query like
select . . . from . . . where xxx in yyy
is such a data type supported by postgresql? do other dbms´s support it?
cheers
frank