Object Oriented Data Model
In this both data and their relationship are organised or contained in a single structure known as object.
Object includes information about relationship between the facts within the object,as well as information about relationship with other objects.
It is also said to be semantic data model.
Components of Object Oriente d Data Model:
An object is the abstraction of the real world entity and an object represents only one occurrence of entity.
Attributes: It describes the property of an object.
Class: Objects that are similar in characteristics are grouped in class.
So large is a collection of similar objects with shared structure(attributes) and behavior (method).
Method: Method represent a real world action such as finding a selected persons name, changing person name, or printing a person address.
Classes are organised in a class hierarchy and it resembles an upside down tree in which class has only one parent(Head).
Inheritance: It is an object ability to inherit the attributes and methods (messages) of the class above it.
In this full time secretary and part-time secretary are attribute and methods of person.