Write the following SQL query:

For each department, list the dno, the bdate of the youngest employee, the bdate of the oldest employee and the difference in the department's maximum employee salary and minimum employee salary. Label these columns Youngest, Oldest and SalDiff, respectively. Sort the results in descending order by SalDiff. NOTE: even though the bdate is stored as a string, you can easily identify the birthdate of the youngest and oldest employee without any type conversion but instead with a simple comparison (i.e., max() and min() work).

The database is as follows: