select replace(reverse(sys_connect_by_path(reverse(rownum || '*' || lv ||
' = ' ||
rpad(rownum * lv, 2) || ' '),
'/')),
'/') rules
from (select level lv from dual connect by level < 10)
where lv = 1
connect by lv + 1 = prior lv




select level lv from dual connect by level < n; 可查询得到1 .. N 的序列