## Sunday, June 06, 2004

### Datalog and Inferencing

Implementing OWL Lite in rule-based systems and recursion-enabled relational DBs "The semantics of negation in stratified Datalog is not compatible with the semantics of negation in Description Logics...Alternative, more compatible semantics for negation in Datalog exist, namely well-founded semantics, that also relies on such a three-valued logics. However, this is not semantics available in SQL:1999 compliant databases. Well-founded semantics only regards the minimal model when computing negation, whereas Description Logics regard all possible models. Hence, they are also incompatible."

Two other related papers: Bubo - Implementing OWL in rule-based systems and Description Logic Programs: Combining Logic Programs with Description Logic.

This maps well to 3VL and the recursive predicate functions trans and walk.