Satisfiability of object-oriented database constraints with set and bag attributes

The definition of methodologies for checking database constraint satisfiability, i.e., the absence of contradictions independently of any database state, is a fundamental and critical problem that has been marginally addressed in the literature. In this paper, a sound and complete algorithm is proposed for checking the satisfiability of a specific class of database integrity constraints in a simplified object-oriented model. Such a class includes cardinality constraints, set and bag attributes, and explicit integrity constraints involving comparison operators. The algorithm, conceived to support database schema design, allows the designer to distinguish among five different kinds of contradictions, each identified by an ad hoc procedure. (C) 2002 Elsevier Science Ltd. All rights reserved.