Significance of a primary key.

Q7. What is the significance of a primary key?
Ans. A primary key is used to uniquely identify which record in a table. In other words, a column with a primary key will not contain duplicate information in any of its records. For example, in the Employee_Details table, we can set the primary key in the Emp_Code column, which contains the employee code. In this case, duplicate values are not possible in the column.