Ontology based data access with referring expressions for logics with the tree model property

Abstract

Certain answer computation for a query has usually entailed the search for constants as substitutions for the query variables that make the query logically entailed by a knowledge base. Such constants are simple examples of referring expressions, that is, syntactic artifacts that identity objects in an underlying domain. In earlier work, we have begun to explore how more general referring expressions can be used to allow more descriptive and useful object identification. In this paper, we present a novel approach to ontology based data access in this more general setting for logics with the so-called tree model property. The proposed solution remedies a problem with our earlier work in certain answer computation with referring expressions in which a process of extending the knowledge base with new constants and assertions that depended on a particular query is required.