You have created a database for employee management. The database has a table named Employees. The
table has the following attributes:
Name
Address
Contact Number
Designation
You want to store the salary information for each employee. The database should also store salary history.
How will you design the database so that you can query the last increment given to a particular employee?
A.
Create a new table that includes the EmployeeSalary and DateOfIncrement columns. Create a one-to-one
relationship with the Employees table.
B.
Create a new table that includes the EmployeeID, EmployeeSalary, and DateOfIncrement columns.
Create a one-to-many relationship with the Employees table.
C.
Add the EmployeeSalary and DateOfIncrement columns to the Employees table.
D.
Create a new table that includes the EmployeeSalary and DateOfIncrement columns. Create a many-tomany relationship with the Employees table using the new table.
Explanation:
It is stated in the question that the database should contain salary history information. This means that the
salary of an employee can be incremented more than once, i.e. a one-to-many relationship exists. To create a
one-to-many relationship between salary and employee, you have to create a separate entity for salary,and
create a foreign key referring to the primary key of the Employees table.
Answer C is incorrect. The creation of the DateOfIncrement column in the table will lead to redundant data.