We will explain here an example database application having COLLEGE database and use it in showing several E-R modelling concepts.

College database remains track of faculty, Students, Departments and Courses organised by several departments. Following is the explanation of COLLEGE database:

College have several departments like Department of Hindi, Department of English, and Department of Computer Science etc. Every department is assigned a unique id and name. Some faculty members are also appointed to each department and one of them works as head of the department (HOD).

There are several courses conducted by every department. Each course is assigned a unique id, name and duration.

• Faculty information has name, address, department, basic salary etc. A faculty member is assigned to only one department but can teach several courses of other department also.
• Student's information contain Name, Roll no (unique), Address etc. A student can opt only for one course.
• Parent (guardian) information is also kept along with every student. We keep each guardian's name, sex, age, and address.