To get Aware IM to calculate the value of an attribute of a business object you have to define a business rule that will perform the required calculation. The rule should be attached to the business object that owns the calculated attribute. See the “Adding/Editing Business Rules” section.

In addition you can check the “Calculated” property of the attribute. This will make sure that the attribute is read-only on the forms of the business object. See the “Adding/Editing Attributes” section.

For example, if you want to define an attribute called NumberOfLineItems in the PurchaseOrder object, you can define the business rule as follows:

If PurchaseOrder.MyLineItems WAS CHANGED Then 
    PurchaseOrder.NumberOfLineItems = COUNT OrderLineItem WHERE 
    OrderLineItem IN PurchaseOrder.MyLineItems