DB2里面哪个Scalar函数可以返回记录集序号的？

[mongmong]

yh_no item_no to_qty
-------------------- -------------------- -----------
YH010302100000 3500000028241 5
YH010302100000 3500000028242 10
YH010302100000 3500000028255 13
YH010302100001 4895025703663 2
YH010302100001 3500000028222 16
YH010302100001 3500000028242 10
YH010302100001 3500000028242 10
YH010302100001 3500000028252 6

想实现如下
autid yh_no item_no to_qty
----- -------------------- -------------------- -----------
1 YH010302100000 3500000028241 5
2 YH010302100000 3500000028242 10
3 YH010302100000 3500000028255 13
1 YH010302100001 4895025703663 2
2 YH010302100001 3500000028222 16
3 YH010302100001 3500000028242 10
4 YH010302100001 3500000028242 10
5 YH010302100001 3500000028252 6

autid应该使用哪个scalar函数生成？

[jiezhi]

row_number() over

[jiezhi]

rank() over

[jiezhi]

select row_number() over (order by yh_no) as autid,item_no,to_qty
from table_name;