An efficient strategy for non-Horn deductive databases

Robert Demolombe
1991 Theoretical Computer Science  
orn Demolombe, R., An efficient strategy for non-Horn deductive databases, Theoretical Computer Science 78 (1991) 245-259. Many efficient strategies have been presented in the literature to derive answers to queries in the context of Deductive Databases. Most of them deal with definite Horn clauses. More recently, strategies have been defined to deal with non-Horn clauses but they adopt the Generalized Closed World Assumption to reduce incompleteness. In this paper we present an efficient
more » ... gy to deal with non-Horn clauses in pure logic, i.e. without any kind of assumption. This strategy is an extension of the so-called ALEXANDRE strategy to this particular context. The set of rules is transfOlilled into another set of rules, in a compilation phase, in such a way that their execution in forward chaining simulates a variant of SL resolution. Particular attention is payed to the constants in the queries to reduce the set of derived clauses.
doi:10.1016/0304-3975(51)90010-2 fatcat:ads47vptqva7hdv4fjw3f36h5i