oracle自定义异常

RAISE_APPLICATION_ERROR( error_num IN NUMBER, error_msg IN VARCHAR2);

		

declare 
v_count number;
begin 
  select count(*) into v_count from dept;
  if v_count < 10 then 
    raise_application_error(-20001,'数量小于10');
  end if;
end;

		

declare 
v_count number;
my_exp exception;
begin 
  select count(*) into v_count from dept;
  if v_count < 10 then 
    raise my_exp;
  end if;
  exception 
    when my_exp then 
      dbms_output.put_line('数量小于10');
    when others then 
      dbms_output.put_line('其他异常');
end;