Specification of the database behavior through the active object paradigm

The paper is concerned with the use of the active object paradigm in designing active databases. The active object is an interesting means to best represent the dynamics of an information system. The authors propose a classification of real world objects following two categories: (i) the persistent active object that describes an object offering services when requested and reacts to events produced in its environment, and (ii) the activity that represents a functionality (or a process) of the information system. The main focus is on the specification of the behavior of an active object through an 'automaton' in agreement with the event-condition-action paradigm. Interactions between objects are modeled by an interaction model inspired by the OMT approach. To illustrate their model, they show how to map the specification of the two active object categories towards a relational implementation.