1. Code an Oracle Database trigger to enforce the constraint that an employee can never change his or her department.
2. Code an Oracle Database trigger to allow the deletion of a department if it only has one employee. Assign the last employee to the Human Resources department.
3. Design a system of triggers to enforce the M-M relationship.
4. as an example, but assume that departments with only one employee can be deleted. Assign the last employee in a department to Human Resources.