SqlServer按半小时分组统计

一、正常的时间格式

SELECT StartTime,CONVERT(datetime,case when datepart(mi,StartTime)<30 then CONVERT(varchar(100),StartTime,23)+ ' ' +datename(hh,StartTime)+':00:00' else CONVERT(varchar(100),StartTime)+':30:00' end) as HourPart 

   FROM

   WGS_MainCDR_201401

   TEMP

   GROUP BY StartTime,StartTime)+':30:00' end)

   

    结果如下：

   StartTime                           HourPart

2014-01-16 01:59:25.203 2014-01-16 01:30:00.000

2014-01-16 01:59:30.627 2014-01-16 01:30:00.000

2014-01-16 01:59:35.297 2014-01-16 01:30:00.000

2014-01-16 01:59:46.063 2014-01-16 01:30:00.000

2014-01-16 02:00:15.327 2014-01-16 02:00:00.000

2014-01-16 02:00:19.157 2014-01-16 02:00:00.000

2014-01-16 02:27:46.327 2014-01-16 02:00:00.000

2014-01-16 02:28:46.327 2014-01-16 02:00:00.000

2014-01-16 02:39:31.000 2014-01-16 02:30:00.000

2014-01-16 02:41:55.843 2014-01-16 02:30:00.000

二、

SELECT case when datepart(mi,StartTime)<30 then datename(hh,StartTime)+':00' else datename(hh,StartTime)+':30' end as HourPart

   FROM

   WGS_MainCDR_201307

   TEMP

   GROUP BY (case when datepart(mi,StartTime)+':30' end)

结果如下：

HourPart

20:00

21:00

10:00

9:30

22:30

13:30

15:30

17:00

三、

select dateadd(mi,(datediff(mi,convert(varchar(10),120),StartTime)),120))

 as '时间段',count(*) as '行数'

from WGS_MainCDR

group by

dateadd(mi,120))