Sybase Powerdesigner 7.5, User Manual

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Chapter 2 Building an Object-Oriented Model
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3 Modify any of the properties of the class directly in the list.
4 Click OK.
Adding objects to a class
You can add an object to a class, that already exists in the model, but which
belongs to another class.
You can add the following objects to an object:
Object Description
Attribute Named property of a class that defines the characteristics of a
class
Operation Implementation of a service that can be requested from any
object of the class in order to affect behavior
Business rule Written statement specifying what the information system must
do or how it must be structured to support business needs
You add an object to a class from the list in the page corresponding to the
object, in the class property sheet.
When you add an object to a class in this way, you in fact create a copy of the
object. The new object exists as a unique object, and you can then make
changes to it as you would to any object in the model.