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When a Decision Rule is executed, it goes through each row and evaluates the Predicate. If the result of the Predicate is true, then is it returns the output parameters accordingly. If none of the cases match, it will return the values defined in the DEFAULT row.
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This predicate will get executed like a normal rule. It's Its input parameters will be those passed into the Decision Rule itself and it will have one predefined output parameter named Result.
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