RE: Data models as constraints

> I have finalized the writeup on data models as constraints. 
> It is available as
> http://koala.ilog.fr/wiki/pub/Main/HassanAitKaci/semwebclp.pdf
> Comments are welcome.

Hassan, it seems that you have completely ignored the 
fundamental issue of negation-as-failure (NaF), also 
called "negation-by-default", and the related issue 
of open vs. closed predicates in your paper. 

Why? Because you didn't consider that (yet) in your 
OSF formalism?

How can you capture SQL, Prolog and production rules
without supporting NaF?

-Gerd