Rewriting-based Check of Chase Termination
Marco Calautti, Sergio Greco, Cristian Molinaro, Irina Trubitsyna · Iris (University of Trento) · 2015
SPARQL entailment regimes are strongly influenced by the big body of works on ontology-based query answering, notably in the area of Description Logics (DLs).However, the semantics of query answering under SPARQL entailment regimes is defined in a more naive and much less expressive way than the certain answer semantics usually adopted in database and DL literature.In this paper we introduce an intuitive certain answer semantics also for SPARQL and show the feasibility of this approach.For OWL 2 QL entailment, we develop algorithms for the evaluation of an interesting fragment of SPARQL (the so-called welldesigned SPARQL).Exploiting these algorithms, we can show that the complexity of neither query answering nor the most fundamental query analysis tasks (such as query containment and equivalence testing) is negatively affected by the presence of OWL 2 QL entailment under the proposed semantics.