1 Relational integrity checking technology can be transfered to deductive object bases by utilizing a simple logical framework for objects. The principles of object identity, aggregation and classification allow a more efficient constraint control by finer granularity of updates, composite updates and semantic constraint simplification. In many cases, meta-level constraints and deductive rules can be handled efficiently by a stepwise compilation approach. An extended integrity subsystem with these features has been implemented in the deductive object base ConceptBase. 1 This work was supported in part by the Commission of the European Community under ESPRIT Basic Research Action 3012 (CompuLog). A version of this paper will also appear in the Proc. Second Int. Conf. on Deductive and Object-Oriented Databases, Munich, Dec. 1991 1. Introduction Comprehensive and efficient integrity maintenance has been quoted as one of the major problems in next-generation databases. Systems l...

1 . Deductive object bases are extended database systems which amalgamate structural object-orientation with logical specification. Queries in such a system are regarded both as classes and as deduction rules. Besides a general architecture for query processing in deductive object bases, two specific query optimization techniques are presented: semantic query optimization with structural axioms of the object base, and view maintenance optimization. The approach has been formalized in the language Telos and implemented in the system ConceptBase. 1 This work has been supported in part by ESPRIT BRA 3012 Compulog. A version of this paper also appears in Freytag, Maier, Vossen (eds.): Query processing in objectoriented, complex-object, and nested relation databases, Morgan Kaufmann, 1992. 1 1. Introduction Traditionally, databases are systems for storing and accessing large amounts of shared persistent data in a secure way. Database research has always been concerned with pro...

The maintenance of semantic integrity has been recognized as a cornerstone issue for the development of databases and knowledge bases alike. Despite the extensive research conducted during the last two decades, semantic integrity maintenance has yet to become a practical technology. Furthermore, the need for modeling evolving domains has given rise to challenging research issues relating to the incorporation of time in knowledge bases. In this thesis, we study the problem of maintaining the integrity of temporal deductive knowledge bases. We argue that existing approaches in either temporal or deductive databases do not address the problem in a satisfactory manner, nor do they deal with all the issues involved in a unified framework. At first, we propose an assertion language that permits us to express different types of temporal assertions that are not expressible in other formalisms. We define the notion of temporal constraint satisfaction in a bitemporal context. We then follow two ...