Re: Distributed foreign keys (was Re: Category Types)

"Paul Vernon" <paul.vernon_at_ukk.ibmm.comm> wrote in message news:bd7bdg$t7g$1_at_gazette.almaden.ibm.com...
> "Bob Badour" <bbadour_at_golden.net> wrote in message
> news:kFFJa.361$ez1.56242211_at_mantis.golden.net...
[snip]
> > > I don't like asymmety, but I don't really see any here. If we take the
> > closed
> > > world assumption, anything that we don't know anything about does not
get
> > > inserted into the database. A distributed foriegn key should not be
> > limited to
> > > the 'complete' case.
> >
> > Why not? What's the point of a foreign key that says a value might or
might
> > not reference a tuple in some relation?

BTW I did not say that. All I said was that in the complete case every value in the PK needs to be a value in on of the FKs as well as ever FK value being a PK value. In the in-complete case, only every FK value needs to a PK value, not vice-versa.

Regards
Paul Vernon
Business Intelligence, IBM Global Services Received on Mon Jun 23 2003 - 19:18:43 CEST