求select查询语句

select dm,lvl from (select dm,lvl,sl from test1 a, (select level lvl from dual connect by level<=(select max(sl)-min(sl)+1 from test1)) b where b.lvl<=a.sl ) t1 where sl is not null; 试着查询了下，如果是上面的数据，查询结果可以出来，不过一直没想好level的条件，这里只用了max(sl)-m