This paper describes our development of the Starburst Rule System, an
active database rules facility integrated into the Starburst extensibl
e relational database system at the IBM Almaden Research Center. The S
tarburst rule language is based on arbitrary database state transition
s rather than tuple- or statement-level changes, yielding a clear and
flexible execution semantics. The rule system has been implemented com
pletely. Its rapid implementation was facilitated by the extensibility
features of Starburst, and rule management and rule processing are in
tegrated into all aspects of database processing.