Optimising Resolution-Based Rewriting Algorithms for DL Ontologies ⋆

Abstract. Resolution-based rewriting algorithms have been widely used for computing disjunctive datalog rewritings for DL TBoxes, and recently, also for computing datalog rewriting for queries over TBoxes expressed in DL-Lite and ELHI. Although such algorithms are general enough to support a wide variety of (even very complex) DLs, this generality comes with performance prices. In the current paper we present a resolution-based (query) rewriting algorithm for ELHI that is based on a hyper-resolution like inference rule and which avoids performing many redundant inferences. We have implemented the algorithm and have conducted an experimental evaluation using large and complex ontologies.