Deriving semantic information through property covering and inheritance

摘要

Covering is a well known relationship in semantic and object-oriented data models. Covering holds when a class is the union of a collection of subclasses. However, covering has been studied only for entity classes. In this paper, we investigate covering for properties, as well. We introduce a new relationship among properties, called property covering. Property covering holds when a property restricted to a given class is the union of a collection of sub-properties. Property covering allows us to (i) partition a property into sub-properties, (ii) express property value refinement, and (iii) express a particular form of negative information. We demonstrate that property covering, together with inheritance, disjointness and participation constraints, constitutes a useful conceptual modeling mechanism. In particular, we provide a set of inference rules that lead to schema derivations based on property covering, specialization and disjointness relations.