Supporting multiple roles through class hierarchies 1
نویسنده
چکیده
Object Oriented Database Systems should allow their objects to play multiple roles and to change roles in their lifetime. We describe a data model, based on classes, is-a hierarchies, and complex types, that allows objects to belong to several classes, so to play multiple roles. Then we propose a declarative query language to access objects from multiple perspectives, and an update language to describe dynamics of objects.
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