>Not at all. The deal is that RI belongs in the DATA SERVICES TIER.

I don't disagree with that statement. It is my considered (and not confused) opinion that RI constitutes a business rule. I understand that most people disagree with me on it.

The discussion has passed in the realm of esoterica, but I appreciate everyone's thoughts.

>I think some of the confusion is that many folks think that RI must be enforced by a trigger mechansim, which is not true at all.

Nope, that is not a point of confusion. At least not for me. Certainly it's valid to point it out.