Creating a Derived Class
To create the derived class that will allow you to return the subjectarea and view associated with each ViewColumn object:
1 Create a derived class with the base class of ViewColumn.
2 Create a derived property called ViewName (which is the name property of the view class), and add it to the newly created derived class.
3 Create a derived property called SubjectAreaName (which is the name property of the subjectarea class), and add it to the newly created derived class.
To the APIs, the derived class will look like a class containing all the properties of the ViewColumn class plus the SubjectAreaName and ViewName properties. A search can be performed on one or more of these properties. The SubjectAreaName and ViewName are returned in the property list in each of the objects in the return list.
There are no physical objects in a derived class. Derived class objects are created by joining properties in a base class with properties in related classes. Therefore derived class objects are read only. You cannot write or delete a derived class object.