PLSQL 异常处理

SET serveroutput ONSET verify ONDECLARE  v_empno emp.employee_id%type := &emp_no;  v_ename emp.first_name%type;  v_deptno dept.department_id%type;  v_dname dept.department_name%type;BEGIN  SELECT first_name,    department_id  INTO v_ename,    v_deptno  FROM emp  WHERE employee_id = v_empno;  SELECT department_name INTO v_dname FROM dept WHERE department_id = v_deptno;  dbms_output.put_line('問合せの社員名は ' || V_ENAME || ' です。' || '所属部門は ' || V_DNAME || ' です。');EXCEPTIONWHEN no_data_found THEN  DBMS_OUTPUT.PUT_LINE('社員番号 ' || V_EMPNO || ' は存在しません');END;