累加问题

SQL code

---有这样一个表create table b(valuess int ,classfiy int ,companyid int)insert into bselect 3,1,1union all select 4,1,1union all select 5,1,1union all select 5,2,1union all select 7,2,1union all select 5,2,1union all select 5,3,1union all select 7,3,1union all select 8,3,1union all select 4,1,2union all select 5,1,2union all select 5,2,2union all select 7,2,2union all select 5,2,2union all select 5,3,2union all select 7,3,2union all select 8,3,2----运行了这下面段出结果select SUM(valuess)vvvvv from b ygroup by companyid,classfiyorder by companyid

vvvvv
----------- 我相要的结果:vvvvv
12 12
17 29
20 49
9 9
17 26
20 46

(6 row(s) affected) 就是将classfiy的小计再累加


[解决办法]
select vvvvv=(select SUM(valuess) from b
where companyid=y.companyid and classfiy<=y.classfiy)
from b y
group by companyid,classfiy
order by companyid