Summary: Durative Events in Active Databases
University of Kent at Canterbury
CT2 7NF, Canterbury, Kent, United Kingdom
Juan Carlos Augusto
School of Computing and Mathematics
University of Ulster at Jordanstown
BT37 0QB Newtownabbey, United Kingdom
Key words: Active databases, event specification language, durative events, composition operators, composition semantics.
Abstract: Active databases are DBMS which are able to detect certain events in the environment and trigger actions in
consequence. Event detection has been subject of much research, and a number of different event specification
languages is extant. However, this is far from being a trivial or accomplished task. Most of these languages
handle just instantaneous events, but it has been noticed that a number of situations arise where it would be
interesting or even necessary to handle durative events. We elaborate on a given specification language which
combines instantaneous and durative events, revealing some issues which must be taken into account when the
semantics of event composition is defined.