Integrating Relational and Object-Oriented Databases in Multidatabase Systems

Abstract

A multidatabase system maintains a global schema that is the integration of component database schemas. This paper proposes an approach to database integration between relational and object-oriented databases in multidatabase systems. We first define correspondence assertions that specify semantic correspondences between schema objects of two component databases. The correspondence assertions are in the form of predicates in the first-order logic. We then present integration rules that describe how to construct the integrated schema according to the specified correspondence assertions. The integration rules consist of algorithmic steps and use primitive integration operators to restructure, transform, and integrate component databases. The primitive integration operators are algebraic operators. The primary objective of our approach is to facilitate the automation of database integration.