This Online Shopping ER Diagram Example is a flowchart or graphical approach that can be used to show how different entities relate to one another. It is a common method for modeling databases and business processes. An ERD comprises several symbols and connections that depict two critical pieces of information: the main entities within the system scope and their inter-relationships. Learn more about this ER Diagram or make your own easily. The ER diagram for the online shopping management system depicts the relationships between the entities that comprise the database design. It can also refer to the logical structure of a system's database or data storage.