Decisions

This is a technical concept. Do not confuse it with the business concept of 'decision' as used in Decision Engines and Decision Modeling and Notation (DMN, the OMG standard first published in 2014). The USoft Rules Engine can act as a Decision Engine, but it is not defined in terms of decision trees or decision calls. Instead, it automatically implements business rules in response to data manipulation events. As such, it is constructed by solely implementing Business Rules and does not need Decision as a modeling concept.

A Decision is declared in the Decisions info window, which clearly shows the 4 attributes that make up a decision:

The decision shown in the picture below uses SQL to retrieve the name of the system directory and concatenate it with a command-line instruction. The result is passed to the operating system (and represented by the :1 placeholder in the Yes Action) for execution. If, for some reason which in this particular situation is not expected, the SQL statement does not yield a result, nothing happens (No Action).

The decision is executed when it is called from an Action Task in a job, from another (or indeed from the same) Decision, from a GUI element in Windows Designer or Web Designer, or from an action script in a SQL Command window. The call from an Action Task looks like this:

The call from an action script in a SQL Command window must used the action keyword to switch from the SQL context to an action context:

To define a decision:

1.	Choose Define, Decisions from the USoft Definer menu. The Decisions window is opened.

2.	Fill out the Decision Name, Decision SQL, Yes Action, and (if used) No Action.

3.	Optionally, press the Check button. This will check that the Decision SQL syntax is correct.

•If the syntax is correct, the Correct flag is set.

•If the syntax is not correct, you get a message and the Correct flag is not set, but you can still execute the decision.

4.	Save work.

To call the decision you have defined, use the ActionDecision() action as outlined earlier in this help topic. For details, see the ActionDecision() help topic in the Developer Reference Guide. You can reach this topic by searching for the action name in the index of the USoft Definer Help.