Illustrate the definition of the classes and operation, Database Management System

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The definition of the classes and operation can often be adjusted to increase the amount of inheritance". Justify the above statement.  

Adjustment of Inheritance

The definition of classes and operations can often be adjusted to increase amount of inheritance among the objects. The object designer can rearrange and adjust classes to increase inheritance between the different objects and classes. Sometimes same operation is defined across several classes and can easily be inherited from the common ancestor. By slightly modifying definitions of the operations or classes, the operation often could be made to match. We also can extract common behaviour out of groups of classes to increase inheritance. Similar attributes in various classes may have different names, but by giving some common name and moving them to the ancestor class we can increase inheritance. An operation may be defined on many different classes in a group but be undefined on other classes. To increase inheritance, we can define it on common ancestor class and declare it as a no-op on classes that do not care about it. We can also use the DELEGATION instead of inheritance to share only meaningful attributes among a super class and its sub class.

 


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