面试之BI-SQL--table转换[2]

month   salesPerMonth

1	2
2	3
3	2
4	4
5	3
6	3

写条SQL语句把上表转成下表：

month   总销量

1             2
2             5
3             7
4             11
5             14
6             17

答案：

selects2.[month],Sum(s1.salesPerMonth)as'总销量'

 FromSaless1,Saless2

 where s1.[month]<=s2.[month]

 Groupbys2.[month]