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What is a Declare Trigger rule in Pega

    • Declare Trigger runs an activity when instances of a specific class are  created, updated, or deleted in the database.
    • This implements a form of forward chaining.
    • For each Declare Trigger rule, the Pega Platform monitors database operations for objects of the Applies To class (and concrete classes derived from that class)
    • During database commit processing, forward chaining processing may trigger — start execution of — the activity identified in this rule.
    • Declare triggers are always executed before the object is committed to the database.
    • Trigger activity can execute immediately or on background .
    •  If you define Declare Trigger's execution method as Background, then Pega creates child requestor and then executes the Declare Trigger in that requestor. The reason for this option is to consider the performance impact of the application.

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