sql使用sum之后如何计算

[zqqazhn]

select sum(cast(b1 as decimal(10,2))) as b1,sum(cast(s1 as decimal(10,2))) as s1 from NB_qy_j

我想计算 b1除以s1.
我的b1是varchar类型.已经用sql语句转换成decimal类型.但不知道怎么计算

[心中的彩虹]

[Quote=引用楼主 zqqazhn 的回复:]
select sum(cast(b1 as decimal(10,2))) as b1,sum(cast(s1 as decimal(10,2))) as s1 from NB_qy_j

我想计算 b1除以s1.
我的b1是varchar类型.已经用sql语句转换成decimal类型.但不知道怎么计算
[/Quote]


直接这样不可以吗
select sum(cast(b1 as decimal(10,2)))/sum(cast(s1 as decimal(10,2))) from NB_qy_j

[obuntu]

--搞个子查询
select b1/s1
from (
select sum(cast(b1 as decimal(10,2))) as b1,sum(cast(s1 as decimal(10,2))) as s1 from NB_qy_j

)

[claro]

。。。

[SQL77]

select sum(cast(b1 as decimal(10,2))) /sum(cast(s1 as decimal(10,2))) as s1 from NB_qy_j

[claro]

[Quote=引用 1 楼 sql77 的回复:]

select sum(cast(b1 as decimal(10,2))) /sum(cast(s1 as decimal(10,2))) as s1 from NB_qy_j
[/Quote]

--修改(回避被零除出错)

select sum(cast(b1 as decimal(10,2))) / NULLIF(sum(cast(s1 as decimal(10,2))),0) as result
from NB_qy_j

http://blog.csdn.net/claro/archive/2009/01/06/3720863.aspx

[htl258_Tony]

select sum(cast(b1 as decimal(10,2)))/nullif(sum(cast(s1 as decimal(10,2))),0) as s from NB_qy_j

考虑除数0值

[zqqazhn]

我要在asp代码里体现出 b1/s1的结果怎么体现.?

[zqqazhn]

我直接写上resposne.write b1/s1 是不行的.

[百年树人]

[Quote=引用 4 楼 zqqazhn 的回复:]
我要在asp代码里体现出 b1/s1的结果怎么体现.?
[/Quote]

select case when s1=0 then 0 else b1/s1 end
from
(
select sum(cast(b1 as decimal(10,2))) as b1,sum(cast(s1 as decimal(10,2))) as s1 
from NB_qy_j
) t

这样？

[永生天地]

[Quote=引用 5 楼 zqqazhn 的回复:]
我直接写上resposne.write b1/s1 是不行的.
[/Quote]
改
resposne.write rs(0)/rs(1)

[hahaxiaoa]

学习下。

[happy664618843]