Defining variables in the rule editor (deprecated)

Variables are defined in the definitions part of a business rule.

Before you begin

Variables are accessible from business rules when you add them to the rule vocabulary. For more information about verbalizing variables, refer to the related topic "Adding and modifying Decision service variables."

About this task

You can use a variable to identify and then refer to an occurrence of something by a convenient name. Use variables to make your business rules clear and easy to understand. When you create a variable in a rule, the variable is only valid for that rule, although the variable can be used in a all parts of the rule. Variable names must be unique within a rule.

Procedure

To define a variable, complete these steps:

  1. In the definitions part of the rule, press Ctrl+Spacebar, and double-click to select set from the Content Assist menu.
    The content of the Content Assist menu changes to show the default name for new variables, variable1. After the definitions are specified, the Content Assist menu changes to show the closing semicolon.
  2. Double-click in the Content Assist menu to insert the placeholder variable name variable1 in the rule.
  3. Type over the placeholder variable name to replace variable1 with the name of your variable.
    If your variable is only one word, quotation marks are not required. If your variable is a phrase containing more than one word, you must put the phrase between quotation marks.
  4. Press Ctrl+Spacebar, and select a variable type from the menu.
    In Business Automation Workflow, every variable name is associated with a variable type, which determines what values are legal for the associated variable. For more information, refer to the related topic "Variable types."
  5. After the variable type is specified, the Content Assist menu changes to show the closing semicolon, or the optional building blocks from, in, and where.
    If you have finished defining the variable, select the closing semicolon. To define a variable using the optional building blocks, continue by selecting from, in, or where.
  6. The variable definition ends with the closing semicolon.
    Once a variable is defined, you can use the variable in all parts of the business rule.

Example

To make a rule easier to read, you can use a variable to define a one-to-one relationship between business objects. In the following business rule, the variable the shopping cart is defined using the one-to-one relationship between two objects: the ShoppingCart and the Customer:
definitions
     set customer to a customer;
     set the cart to the shopping cart of customer;
if
the value of the cart is less than $100
then
apply 10% discount;

What to do next

You must initialize complex variable structures before running the Decision service. In Business Automation Workflow, all complex variables and all lists (arrays) must be initialized before you use them in a BPD or service. If you do not initialize a complex variable or list, you may receive runtime errors or notice that the controls to which the variables are bound do not behave as expected. For more information, refer to the related topic, "Initializing complex variables and lists."