Explaining DMN core elements

Objective

After completing this lesson, you will be able to explain DMN core elements.

DMN Core Elements

DMN Core Elements.
DecisionInput dataKnowledge source
  • Uses logic to determine an outcome
  • Contains business rules
  • Can be decomposed into sub-decisions and reused
  • Provides information for decisions
  • Has an associated data type
  • Can be used by different decisions
  • Prescribes knowledge for decisions
  • Can be a regulation, law, or authoritative source
DecisionInput dataKnowledge source

To model a decision

Steps

  1. Identify decisions or business requirements:

    • Objectives
    • Questions and answers
  2. Gather decision requirements:

    • Information needed to answer the question
    • Knowledge sources 
    • Regulations 
    • External authorities, for example, government legislators
  3. Break decisions down into sub-decisions.

Our First Decision: Determine How to Eat Dinner

Summary

Decision diagrams answer the following questions in a clear schematic way:

  • What are the decision requirements?
  • Are there sub-decisions?
  • Are internal or external guidelines for decisions needed?
  • What are the dependencies between decisions and/or input data?

This is an example of a decision diagram. The elements of the diagram will be explained in more detail during the following lessons.

Let's take a look at how to build a decision model in DMN. We'll use the decision example how to eat dinner based on available budget and motivation. Watch the video below to see how it's done.