How Does The Concept Of An Object In The Object-oriented Model Differ

1.	How Does The Concept Of An Object In The Object-oriented Model Differ From The Concept Of An Entity In The Entity-relationship Model?
Answer» An ENTITY is simply a collection of variables or data items. An object is an encapsulation of data as WELL as the methods (CODE) to OPERATE on the data. The data MEMBERS of an object are directly visible only to its methods. The outside world can gain access to the object’s data only by passing pre-defined messages to it, and these messages are implemented by the methods. An entity is simply a collection of variables or data items. An object is an encapsulation of data as well as the methods (code) to operate on the data. The data members of an object are directly visible only to its methods. The outside world can gain access to the object’s data only by passing pre-defined messages to it, and these messages are implemented by the methods.

How Does The Concept Of An Object In The Object-oriented Model Differ From The Concept Of An Entity In The Entity-relationship Model?

Answer»

An ENTITY is simply a collection of variables or data items. An object is an encapsulation of data as WELL as the methods (CODE) to OPERATE on the data. The data MEMBERS of an object are directly visible only to its methods. The outside world can gain access to the object’s data only by passing pre-defined messages to it, and these messages are implemented by the methods.

An entity is simply a collection of variables or data items. An object is an encapsulation of data as well as the methods (code) to operate on the data. The data members of an object are directly visible only to its methods. The outside world can gain access to the object’s data only by passing pre-defined messages to it, and these messages are implemented by the methods.

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