Figure 6: Raise_Error signals exception if invalid job_type is encountered

SELECT emp_name,

   CASE job_type 

       WHEN 1 THEN 'Programmer'

       WHEN 2 THEN 'Administrator'

       WHEN 3 THEN 'Project Manager'

       WHEN 4 THEN 'Manager'

        ELSE RAISE_ERROR('70001', 'Invalid JobType') END

  FROM employee