I certainly appreciate this discussion and the clear opinions of Mike.
Somehow it turned my somewhat simple question into something much more
I believe in referential integrity, I also believe that enforcing a
"fully saturated" data model like Mike proposes, is a constraint on
data modeling that is not acceptable for me. Orphans exist in my (data
modeling) world, and arguing about the validity of that will probably
just end up in discussing contrived examples.
Anyway, thanks for sharing your opinions Mike. Oracle could have used
you when the implemented the empty string... :-)