Entity Relationship Diagram 4.4

 The diagram above shows an example of an Entity Relationship Diagram. The first entity describes the specifics of the invoice. In an invoice it has different records that contains the customers information. Each record contains attributes that describes what the customer purchases, or just basic information about that customer. The customers information is usually entered into an database table holding their data. The diagram above shows the relationship between the information on the invoice, and the information of the customer and the information and description of the product that the customer purchases.