Active databases extend database management with production rules.
They are integrated systems which support reactive processing, i.e. the autonomous reaction of the system to events causing changes in the database state. Research is focused on suitable language extensions for supporting production rules inside a database systems, on characterizing precisely the semantics of active systems, and on providing techniques for their efficient implementation. The prototype is being used to experiment with innovative uses of active rules for authorization checking, derived data maintenance, workflow management, configuration management, production control, stock market control, and so on.