An entity-relationship diagram is a graphical representation of the entities (tables) in a database. It is used to illustrate the relationship that exists between two or more entities.

 

 

 

 

 

Below is an illustration of a Entity Relational Diagram (ERD) with the Entities and their attributes

 

 

 

 

 

 

One Course teaches many pupils

• The Primary Keys in both tables must be underline
• The Foreign Key in the many table must have an asterisks *
• The side of the ERD that has the Foreign Key will be the many side and will be illustrated with the crows feet
• The relationship must always be described (teaches)