Ontology-based data access: A study through disjunctive datalog, CSP, and MMSNP

Meghyn Bienvenu (1) , Balder ten Cate (2) , Carsten Lutz (3) , Frank Wolter (4)

1 IASI (LRI) - Intelligence Artificielle et Systèmes d’Inférence
2 UC Santa Cruz - University of California [Santa Cruz]
3 Computer science departement [Bremen]
4 Department of Computer Science [Liverpool]

Ontology-based data access is concerned with querying incomplete data sources in the presence of domain-specific knowledge provided by an ontology. A central notion in this setting is that of an ontology-mediated query, which is a database query coupled with an ontology. In this paper, we study several classes of ontology-mediated queries, where the database queries are given as some form of conjunctive query and the ontologies are formulated in description logics or other relevant fragments of first-order logic, such as the guarded fragment and the unary-negation fragment. The contributions of the paper are three-fold. First, we characterize the expressive power of ontology-mediated queries in terms of fragments of disjunctive datalog. Second, we establish intimate connections between ontology-mediated queries and constraint satisfaction problems (CSPs) and their logical generalization, MMSNP formulas. Third, we exploit these connections to obtain new results regarding (i) first-order rewritability and datalog-rewritability of ontology-mediated queries, (ii) P/NP dichotomies for ontology-mediated queries, and (iii) the query containment problem for ontology-mediated queries.

Domaines: Base de données [cs.DB]; Logique en informatique [cs.LO]; Intelligence artificielle [cs.AI]

Meghyn Bienvenu, Balder ten Cate, Carsten Lutz, Frank Wolter. Ontology-based data access: A study through disjunctive datalog, CSP, and MMSNP. ACM SIGMOD-SIGACT-SIGART Symposium on Principles of Database Systems (PODS), Jun 2013, United States. ⟨hal-00833307⟩