ERD

ERD :-

An ERD is a graphical model of information system that describes the relationship among the system entities. ERD is a major data in our project into entities and define the relationship between the entities.

Components of ERD :- An ERD has 4 major graphical components:

1st entity:- A data entity is anything read or abstract about which we want to solve and stored in a particular project for example employee’s books, computers etc.

2nd entity:- A data relationship is a natural association that exists between one or more entities.

3rd attribute:- An attribute is a characteristic of any particular entity which we can explain in our practical file, for example if we consider the entity is an employee, then the attribute are emp_name, emp_address emp_id designation etc.

4th cardinality:- It is the specific no of occurrence from one object to another object or one entity to another entity for a particular description.


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Article by
St.Mary's Group
CSE Dept.