Supporting physical independence in an object database server

An approach for supporting physical independence in Object Database Servers is proposed in this paper. While in current implementations the strategy for storing data objects reflects the logical object definitions, a certain degree of independence in the physical database organization would be essential to meet specific performance requirements. In this paper, a canonical object data model and a storage object data model are presented. In the first, the objects are organized in classes; in the second, physical objects with similar structures are grouped in collections. Mechanisms for mapping data structures and operations from the logical level to the physical level are discussed, and a comprehensive example is given.