Domains for z/OS data models

You can create domains for rule projects, which are based on data items that are defined in the z/OS® data models (COBOL copybook or PL/I include file).

Domains restrict the values of a BOM element to a set of predefined values. The values that are used for setting variables in programming code are often not values that are suitable to use in rule authoring.

For example, in COBOL, the color attribute of an object might be represented by a numeric code rather than in natural language. To write rules more easily, you can create a COBOL domain for verbalized simple attributes and their corresponding coded values.

You can use the verbalized attributes when you write your rules, and then at run time each verbalized attribute is replaced by its corresponding coded value.

For example, suppose you have a copybook that contains the following data items:

05 country PIC X(2).
05 color PIC 9(12).

You can define a domain named country that has a set of values such as {Germany, France, Italie}, and a domain named color that has a set of values such as {Red, Blue, Yellow}.

To convert a data item to a domain type, you use the type converter during the XOM creation process.

You can also define a dynamic domain in an Excel spreadsheet for the COBOL code generation approach.