D.A. Nelson
B.N. Rossiter
University of Newcastle upon Tyne. 1995.
This paper is concerned with a formal model for object databases. Category theory is used to define the Product model, a formal notation for representing features of an object based database. In particular, we will examine how this model deals with three of the most important problems inherent in object databases, those of queries, closure and views, as well as how our model deals with more common database concepts, such as keys, relationships, aggregation, etc. We will implement a prototype of this model using P/FDM, a semantic data model database system based on the functional model of Shipman, with object-oriented extensions.