DERIVING INCREMENTAL PRODUCTION RULES FOR DEDUCTIVE DATA

We show that the production rule mechanism provided by active database systems can be used to quickly and easily implement the logic rule interface of deductive database systems. Deductive rules specify derived relations-using Datalog with built-in predicates and stratified negation; the deductive rules are compiled automatically into production rules. We present a materialized approach, in which the derived relations are stored in the database and the production rules automatically and incrementally propagate base relation changes to the derived relations. We also present a non-materialized approach, in which the production rules compute the derived relations on demand.