Integrating Active Concepts into an Object-Oriented Database System

This paper describes the active, object-oriented database system SAMOS being developed as a research prototype. Its main approach is the integration of rules in the sense of active database systems into a general object-oriented data model. Our effort is also focussed on integrating the rule system with transaction processing in a meaningful way. 1 Introduction Object-oriented database systems (ooDBS) aim at representing more real-world semantics in the database than conventional ones; to this end, they provide mechanisms to model complex structures and to express userdefined (procedural) behavior. Active database systems are able to recognize specific situations (in the database and beyond) and to react to them without direct explicit user or application requests. The association between situations and (re)actions is specified by means of production rules. Thus, active databases allow to represent (a different kind of) real-world semantics, too, that are otherwise hidden in applicati..