DMN13 — Bug in specification of the ‘Any’ Hit Policy

The purpose of the ‘Any’ Hit Policy is to allow for overlapping criteria in the rule conditions for the same conclusion. However, each rule also needs to allow for different additional information and messages that are specific to that rule. See attached example decision table. The current text in the specification does not allow for this.

Currently, ‘Any’ is defined in section 8.2.11 as: “Any: there may be overlap, but all of the matching rules show equal output entries for each output, so any match can be used. If the output entries are non-equal, the hit policy is incorrect and the result is undefined. “

Proposal to change the above text to: “Any: there may be overlap, but all of the matching rules show equal output entries for the left-most output column, so any match can be used. If the output entries are non-equal for the left-most output column, the hit policy is incorrect and the result is undefined.“

DMN 1.2 provides annotation columns as well as result columns

annotation columns are not considered in hit policy semantics, they can differ for the ANY policy