- Write a query to list the employees first, and last name as well as their hire date and commission_pct. If the commission_pct is empty report 0 instead. Order by Last name alphabetically in ascending order.
NVL(commission_pct, 0)
3. Find the average salary of employees
Use avg(salary)
5. Count all the departments and also count all the departments without a manager.
Use count(*)