Integrity Verification in Knowledge Bases

ABSTlZACT In order to faithfully describe real-life applications, knowledge bases have to manage general integrity constraints. In this article, we analyse methods for an efficient verification of integrity constraints in updated knowledge bases. These methods rely on the satisfaction of the integrity constraints before the update for simplifying their evaluation in the updated knowledge base. During the last few years, an increasing amount of publications has been devoted to various aspects of this problem. Since they use distinct formalisms and different terminologies, they are di~cult to compare. Moreover, it is often complex to recognize commonalities and to find out whether techniques described in different articles are in principle different. A first part of this report aims at giving a comprehensive state-of-the-art in integrity verification. It describes integrity constraint verification techniques in a common formalism. A second part of this report is devoted to comparing several proposals. The differences and similarities between various methods are investigated.