Active Database Architectures and the Design of Sentinel for Constraint Management.

摘要

Over the last few years active databases have become an important research area geared towards meeting of the requirements of a variety of non-traditional applications. This report concentrates on providing a seamless incorporation of events and rules into an OODBMS with an emphasis on the modularity and extensibility of the resulting system. The report extends the monitoring view point to an external one, thereby allowing objects to monitor and react to changes occurring to their own state as well as changes occurring to other objects. This is accomplished by introducing a reactive asynchronous object interface. This interface enables objects to propagate pre-declared events occurring to their state to other objects, thereby enabling other objects to perform operations. In addition, a subscription and notification mechanism is introduced that allows event notification to be specified dynamically. This mechanism enables objects to selectively monitor other objects at run-time using the reactive interface. A design is proposed for the specification and detection of simple as well as complex events. This report combines the strengths of the approaches taken in Ode and ADAM and extends them in several significant ways. Databases, Computers, Artificial intelligence, Knowledge-based, Software.