sql server每日平均值

Question

什么是获得每日平均水平的最佳方式.数据每天有2个值,例如:

Date             Value
1/1/2012 4:00    10.00
1/1/2012 16:00   11.00
1/2/2012 4:00    11.22
1/2/2012 16:00   13.55
etc.

Answer 1

Select CAST(DateColumn as date), AVG(Value)
From Table
Group By CAST(DateColumn as date)