SQLServerの行番号で内部結合を行う方法

これを試してください：

SQL Server 2008でROW_NUMBER（）関数を使用する

select A.val,B.val 
from(
    SELECT val,row_number() over (order by val) as row_num
    FROM A)A
join
    (SELECT val,row_number() over (order by val) as row_num
    FROM B)B
on  A.row_num=B.row_num
ORDER BY A.val,B.val

SQLフィドルデモ