Handling Exceptions: An Example

Example

CREATE OR REPLACE PROCEDURE raise_salary
   (p_id IN employees.employee_id%TYPE,
    p_percent IN NUMBER)
IS
    e_toomuch EXCEPTION;
BEGIN
    IF p_percent >= .30 THEN
      RAISE e_toomuch;
    END IF;
    UPDATE employees
    SET salary = salary * (1 + p_percent/100)
    WHERE employee_id = p_id;
EXCEPTION
    WHEN e_toomuch THEN
      dbms_output.put_line('Amount is too high.');
    WHEN OTHERS THEN
      dbms_output.put_line('Error: raise not processed.');
END raise_salary;
/

• The exception is defined in the declarative section.
• If the raise amount passed into the procedure is greater than .30 (30%), then the error is raised and control of the program passes the the EXCEPTION area.
• The EXCEPTION section checks for the error type. If the error raised is e_toomuch, a customized message is displayed.
• The OTHERS clause catches for any other exceptions that may occur in this PL/SQL block.