Database Management System Emulation - Information Systems Reengineering, Integration and Normalization - page 253

will create an new instance of class department. The example is passing a message
to DEPARTMENT class object without directly operating on their attribute values.

Inheritance Attributes and methods were inherited from its superclass, and added
new attributes and methods for the inherited object. For example,

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will display all instances which belong to class ft_student.

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Polymorphism
The same method call will give different results on different class objects. For
example,

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will have different results. The following result will be displayed on the screen:

Abstract Data Type and Multiple Values The type of an attribute can be defined as
any predefined class or as a set of objects. For example, in the prototype CLASS
course, the attribute method

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Call set_of_student_registered(course_no)