Active Database Knowledge Model
The knowledge model of an active database describes what can be said about the ECA rules, that is, what types of events are supported, what types of conditions are supported, and what types of actions are supported?
The knowledge model describes what types of events, conditions, and actions are supported in an active database. Another way to look at the knowledge model is to imagine what types of features are available in an ECA rule definition language.
A framework of dimensions for the knowledge model is presented in . Briefly, each part of an ECA rule is associated with dimensions that describe supported features. Thus, an event can be described as either a primitive event or a composite event, how it was generated (source), whether the event is generated for all instances in a given set or only for a subset (event granularity), and what types (if event is a composite event) of operators and event consumption modes are used in the detection of the composite...
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