A path finding method for constraint checking in deductive databases

摘要

A method is presented for checking integrity constraints in a deductive database in which verification of the integrity constraints in the updated database is reduced to the process of constructing paths from update literals to the heads of integrity constraints. In constructing such paths, the method takes advantage of the assumption that the database satisfies the integrity constraints prior to the update. If such a path can be constructed, the integrity of the database has been violated. Correctness of the method has been proved for checking integrity constraints in stratified deductive databases. An explanation of how this method may be realised efficiently in Prolog is given.