Data model issues for object-oriented applications

摘要: Presented in this paper is the data model for ORION, a prototype database system that adds persistence and sharability to objects created manipulated object-oriented applications. The ORION consolidates modifies number of major concepts found many systems, such as objects, classes, class lattice, methods, inheritance. These are reviewed three enhancements conventional model, namely, schema evolution, composite versions, elaborated upon. Schema evolution ability dynamically make changes definitions structure lattice. Composite recursive collections exclusive components treated units storage, retrieval, integrity enforcement. Versions variations same object related by history their derivation. strongly motivated management requirements applications from domains artificial intelligence, computer-aided design manufacturing, office information systems with multimedia documents.