Question

我是sql server的初学者，编写此查询以从表中选择任何数据：

select   phoneNumber,sum(Duration) sumPrice
    from CDR
    where Date_>=@var1 and Time>@var2
    group by phoneNumber

查询返回大约800万条记录，我想将最后一条记录时间字段保存到其他变量中，例如：

select   phoneNumber,sum(Duration) sumPrice
from CDR
where Date_>=@var1 and Time>@var2
group by phoneNumber
@Time=last up query time column

我该怎么写呢？感谢每一个人。

Answer 1

Declare @Date Date,@Time Time  -- Assuming a Time field 

Select Top 1 @Date=Date_,@Time=Time
  From CDR
  Where Date_>=@var1 and Time>@var2
  Order By Date_ Desc, Time Desc

Select @Date,@Time

Answer 2

试试这个：

Set @Time = (Select Top 1 Time
  From CDR
  Where Date_>=@var1 and Time>@var2
  Order By Date_ Desc, Time Desc)

如果您需要选择更多列，则需要使用：

Select Top 1 @Time=Time, Col1, Col2
From CDR
Where Date_>=@var1 and Time>@var2
Order By Date_ Desc, Time Desc

如何从select查询中将最后一条记录保存到变量中？

2 个答案: