Support ticket priority (DMN)

The classic support matrix, written as a decision table so it can be executed rather than argued about.


#What this example shows

  • Two ordinal inputs producing one output.

  • A complete matrix with no gaps.

  • An output that also carries the response target.


#Columns

Column

Type and meaning

Impact (input)

string: low, medium or high

Urgency (input)

string: low, medium or high

Priority (output)

string: P1 to P4

Response (output)

string: target first response


#The decision table

Hit policy: U (Unique). Cells are FEEL expressions, so a range, a list or a negation is a legal value; a dash means the input is irrelevant to that rule.

Impact

Urgency

Priority

Response

"high"

"high"

"P1"

"15 minutes"

"high"

"medium"

"P2"

"1 hour"

"high"

"low"

"P3"

"1 working day"

"medium"

"high"

"P2"

"1 hour"

"medium"

"medium"

"P3"

"1 working day"

"medium"

"low"

"P4"

"3 working days"

"low"

"high"

"P3"

"1 working day"

"low"

"medium"

"P4"

"3 working days"

"low"

"low"

"P4"

"3 working days"


#Making it your own

  • Two outputs in one table is fine and keeps the priority and the target together.

  • Set allowed values on both inputs so only the nine combinations are possible.

  • A complete matrix has no catch-all row, which is how you know it is complete.



The hit policy is the whole decision.