这个语句怎么写？

[zhangwei1437]

数据库中有一个表a，其中有一个字段是date，里面存的日期格式是‘年月日时分秒’，还有一个数量字段，我如何把在某一天的数据求和啊？
date shu

2004-7-4-8-56-30 10
2004-7-4-9-23-30 20
2004-7-5-12-20-20 5
2004-7-5-12-20-52 10

[victorycyz]

把日期字段改成datetime型就好办了。

[zheninchangjiang]

select [date]=convert(varchar(10),[date],120),sum(shu) as shu from a group by
convert(varchar(10),[date],120)

[pbsql]

select convert(varchar(10),[date],120) 'date',sum(shu) shu
from a group by convert(varchar(10),[date],120)

[zheninchangjiang]

看错了

[zheninchangjiang]

select [date]=substring(date,1,(case
when substring(date,9,1)='-' then 8 else charindex('-',date,9)-1 end)),sum(shu) as shu from a
group by substring(date,1,(case
when substring(date,9,1)='-' then 8 else charindex('-',date,9)-1 end))

[zhangwei1437]

谢谢各位大侠，我只能给这些分了，下次多给