NF2 Relational Model and Attribute Inheritance.

摘要

The discussion in this paper is based on the concept of shallow-equal. This is consistent with the idea of complex object views in Starburst, supporting the sharing of nested component in NF(sup 2) relations. It is not difficult to find out that the discussions in this paper still hold in the concept of deep-equal. Based on NF(sup 2) relational model with composite tuple identity, this paper discusses the concept of class, subclass, s-class, attribute inheritance, providing a kind of formal definitions. The semantics is clear, and can reflect the real world. It has enriched the theory of O-O Model and NF(sup 2) relation model, it is also important to combine the value-based model with the O-O model.