PL/SQL有关问题，大侠帮帮忙！_Oracle开发

PL/SQL问题，大侠帮帮忙！急急急！
帮我写个PL/SQL块，也就是说把下面这句话循环执行1500次。数据是
1F001
1F002
这样加的
INSERT INTO room(num) VALUES ('1F001');
效果如下
1F001
1F002
1F003
1F004
1F005
……
……
1F1500

------解决方案--------------------

SQL code

DECLARE  I INTEGER;BEGIN  FOR I IN 997 .. 1002 LOOP    IF LENGTH(I) < 3 THEN      INSERT INTO ROOM (NUM) VALUES ('1F' || LPAD(I, 3, '0'));    ELSE      INSERT INTO ROOM (NUM) VALUES ('1F' || TO_CHAR(I));    END IF;  END LOOP;END;/
------解决方案--------------------
SQL codeINSERT INTO room  (num)  select '1F'||reverse(substr(reverse('000' || rownum), 1, 4)) as num    from system.help t1, system.help t2   where rownum <= 1500
------解决方案--------------------
DECLARE
 I INTEGER：=1;
BEGIN
 LOOP
   INSERT INTO ROOM (NUM) VALUES ('1F' || LPAD(I, decode(length(to_char(i)),4,4,3), '0'));
   exit when i=1500;
   i:=i+1
 END LOOP;
END;