Fachbereich Informatik, Universität Dortmund, D-4600 Dortmund 50, West Germany
Abstract: We describe the architecture of a relational database system that is extensible by user-defined data types and operations, including relation operations. The central concept is to use languages based on many-sorted algebra to represent queries as well as query execution plans. This leads to a simple and clean extensible system architecture, eases the task of an application developer by providing a uniform framework, and also simplifies rule-based optimization. As a case study the extensions needed for a geometric database system are considered.
Published: In: P.G. Apers and G. Wiederhold (eds.), Proc. of the 15th Intl. Conf. on Very Large Databases, Amsterdam, 1989, 33-44.