Transparent Evolution and Integration of Classes in Object-Oriented Databases
نویسنده
چکیده
Object-oriented databases have limited support for evolution at the schema level. This paper presents a framework for transparent class evolution and integration, which unifies existing evolution techniques, like subclassing, generalisation, class versioning, and integration by views. The transparency offered allows existing and new clients of classes to be unchanged upon evolution and integration of populated classes. This is done by separating the extensional and intensional dimensions of classes into two different hierarchies, and by having external constructs for describing interdependencies between the properties of the classes.
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