Simulating a Decision Service

Decision Services can be simulated in the same way that other decisions are simulated. The starting point is as always to drag-and-drop a DMN Simulation Configuration Artifact onto the diagram, and then select the Decision to act as the starting point and any Input Data sets required.

By default, all Decision Service elements and every discrete Decision are listed for selection in the drop-down field in the dialog toolbar.

The input data and decisions are in the correct execution order. For example, 'Application risk score' will be executed before 'Post-bureau risk category', 'Post bureau affordability' and 'Routing'. This follows the principle of the decision hierarchy, which starts at the roots and moves to the trunk (the highest level Decision that has been selected). After providing the input data by choosing a data set in the combo box, click on the Save icon and on the button on the toolbar.

This diagram shows the result of the simulation, which allows the simulation audience to visualize how the final decision was arrived at by annotating the diagram with the intermediate decisions and input data. It is also possible, once the simulation has been run, to step through the simulation and see how each decision was reached, including the visualization of the rules and expressions in the Decision Expression Editor. For example, if an expression has been defined using a Decision Table, the rule or rules that are hit will be highlighted allowing the audience to understand the logic as it is applied - and potentially correct errors or oversights.