An Evolutionary Approach for Dynamic Reconfiguration in Heterogeneous Database Schemas

Most information systems share an architectural style that emphasizes flexibility and run-time adaptability. However, any knowledge or business rules related to the information are stored implicitly to the external programs such as database. It can be called "semantics" that they have a definition of a domain model and rules for its integrity and can be configured by domain experts external to the execution of the program. Therefore, heterogeneous database schemas which have different information or knowledge each other should be integrated to present relevant information consistently. In this paper a semantic approach for the specification and the management of databases with evolving schemata is introduced. It is shown how a general object-oriented model for schema versioning and evolution can be formalized. We show how the semantics of schema change operations can be defined, and how interesting reasoning tasks can be supported, based on an encoding in description logics.