Data abstractions: Why and how?

The relational data model has become the standard for mainstream database p rocessing despite its well-known weakness in the area of representing appli cation semantics. The research community's response to this situation has b een the development of a collection of semantic data models that allow more of the meaning of information to be represented in a database. The primary tool for accomplishing this has been the use of various data abstractions, most commonly: inclusion, aggregation and association. This paper develops a general model for analyzing data abstractions, and then applies it to th ese three best-known abstractions. (C) 1999 Elsevier Science B.V. All right s reserved.