Definition – What does ER Diagram mean?
Entity Relationship Diagram is a data modelling technique that graphically shows the relationship between the people, place, objects or events within that system, first introduced in 1976 designed by Peter Chen on paper. It is the best technique that can help define business processes and can be used as the foundation of the relational database.
Glossary Web explains ER Diagram
There are total three different elements of an ERD technique such as Entities, Relationship and Attributes, and the step involved identifying and defining the entities, determine all the instructions, analyzing nature of the interactions of the relationship and creating complete ERD. An entity is a real-world item or concept that exists on its own. All the entities are equivalent to a database table in a relational database, with each row of the database table shows an instance of that entity. The attribute of an entity is a particular property that describes that entity. A relationship is an association that describes the interaction between entities.
It is a useful technique that is best for any kind of businesses or companies. For example, the diagram easily representing the information system for a company’s sales department might start with the graphical representations of entities such as the sale representative, customer, customer orders and the products etc. Then the lines or other suitable symbols can be used to represent the relationship between entities and text.