This is an ER diagram example that illustrates the use of all three additional entity sets listed.
• course with attributes name, department, and c-number
• section with attributes s-number and enrolment, and dependent as a weak entity set on course
• room with attributes r-number, capacity, and building
Entity Relationship Diagram (ERD) or Entity Relationship Diagram (ERD) is a diagram that shows the relationship between entity sets contained in a database. In other words, ER diagrams aid in the explanation of database logical structure. Entities, attributes, and relationships are the three main notions that ER diagrams are built on.