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Explicit Event

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In active databases, an explicit event is explicitly specified in the ECA rule definition.

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ECA rules were developed as an optimization of condition action rules. The performance of rule evaluation was improved by allowing, or even requiring, explicit definition of when rules should be triggered in the form of events. For example, (ON update A followed_by update B IF A = 5∧ B = 3 DO action) is a rule specification that is triggered by the explicit event update A followed_by update B (i.e., a sequence of updates).


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Correspondence to Jonas Mellin .

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Mellin, J., Berndtsson, M. (2017). Explicit Event. In: Liu, L., Özsu, M. (eds) Encyclopedia of Database Systems. Springer, New York, NY.

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  • Print ISBN: 978-1-4899-7993-3

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