10A.53 Code an Oracle Database trigger to enforce the constraint that an employee can
never change his or her department.
10A.54 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.
10A.55 Design a system of triggers to enforce the M-M relationship. Use Figure 10A-53 as an
example, but assume that departments with only one employee can be deleted.
Assign the last employee in a department to Human Resources.