Customizeed sorting order

To sort this table Employee by department, you would use ORDER BY Department. However, if you want a different sort order that is not alphabetical, you have to map the Department values into different values that sort correctly; this can be done with a CASE expression:

Name | Department |
—–– | ––––– |
Hasan | IT |
Yusuf | HR |
Hillary | HR |
Joe | IT |
Merry | HR |
Ken | Accountant |

SELECT *
FROM Employee
ORDER BY CASE Department
         WHEN 'HR'         THEN 1
         WHEN 'Accountant' THEN 2
         ELSE                   3
         END;

Name | Department |
—–– | ––––––– |
Yusuf | HR |
Hillary | HR |
Merry | HR |
Ken | Accountant |
Hasan | IT |
Joe | IT |