You work as a Database Designer for Allen Inc. You are designing the database of a company that has several
divisions (e.g. Spare Parts division). Each division has several departments (e.g. Quality Control department),
and every department has several employees. What will be the relationship between the two entities, namely,
division and employee, if you model the database?

A.
No direct relationship

B.
One-to-one

C.
Many-to-many

D.
One-to-many

Explanation:
There is no direct relationship between the two entities: division and employee. In the given scenario, the
relationship is as follows: There exists a one-to-many relationship between division and department. There
exists a one-to-many relationship between department and employee. Answer B is incorrect. In a one-to-one
relationship, every instance of the first entity has only one instance of the second entity. For example, in an
organization, every department such as Sales has only one Senior Manager, and all the other employees in the
Sales department work under him. This relationship between the Sales department and the Senior Manageris
one-to-one. Answer D is incorrect. In a one-to-manyrelationship, every instance of the first entity can have
more than one instance of the second entity, but for the instance of the second entity, there is exactly one
instance of the first entity. For example, the relationship between Department and Employee is one-to-many.
There are many employees working in a department (e.g. Sales). Answer C is incorrect. In a many-to-many
relationship, every instance of the first entity can have multiple instances of the second entity, andevery
instance of the second entity can also have more than one instance of the first entity. For example, acustomer
can purchase more than one product, and a product can also be sold to several customers.