微信扫一扫3.3w+
社区成员
这样的查询语句让我伤脑筋？只得向各位请教了，救命啊！！！！
现有这样的查询语句：
select ID, Sum(Degree)/Sum(Weight) as dw from DegreeTable
group by ID.
但是，如果Sum(Weight)为零的话，我想执行下面的语句，因为除数不允许为零。
select ID, Sum(Degree) from DegreeTable group by ID.
怎么把两个语句合成一个SQL语句啊？
select ID, Sum(Degree)/Sum(Weight) as dw from DegreeTable
group by ID.
但是，如果Sum(Weight)为零的话，我想执行下面的语句，因为除数不允许为零。
select ID, Sum(Degree) from DegreeTable group by ID.
怎么把两个语句合成一个SQL语句啊？
...全文
当前发帖距今超过3年，不再开放新的回复
发表回复
licher 2004-04-29
我先试试。等下结分。
- 打赏
- 举报
csdnwhycn 2004-04-29
同意楼上
- 打赏
- 举报
outwindows 2004-04-29
select ID,
Sum(Degree)/( case when Sum(Weight)=0 then 1 else Sum(Weight) end ) as dw
from DegreeTable
group by ID.
Sum(Degree)/( case when Sum(Weight)=0 then 1 else Sum(Weight) end ) as dw
from DegreeTable
group by ID.
- 打赏
- 举报
zjcxc 元老 2004-04-29
select ID,case Sum(Weight) when 0 then Sum(Degree) else Sum(Degree)/Sum(Weight) end as dw from DegreeTable
group by ID
group by ID
- 打赏
- 举报
three.js 入门示例，含坐标系、相机参数 three.js 入门示例，含坐标系、相机参数
对应博客地址：
https://blog.csdn.net/u010476739/article/details/122597958
