《按每天，某个时间段》
select A,B,C,DATETIME,CAST(CONVERT(varchar(100), DATETIME, 112) AS INT ) AS daytime
from TABLE1
WHERE 1=1
AND CAST(DATETIME AS TIME) BETWEEN '21:00:00' AND '23:59:59'
AND DATETIME>='2016-07-11' and DATETIME<'2016-07-15'
group by A,B,C,DATETIME
---------------------------------------------
《WITH AS 递归获取部门梯队》
WITH dtTree
AS (
SELECT * FROM table1 ur
WHERE DepartId = 0
UNION ALL --第二个查询作为递归成员， 下属成员的结果为空时，此递归结束。
SELECT urTree.* FROM dtTree
INNER JOIN table1 urTree
ON dtTree.DepartId = urTree.DepartId and urTree.NAME =dtTree.NAME
)
---------------------------------------------
《LINQ 合并集合后分组某一个字段》
List<AppCallStatisticsModel> data3 = new List<AppCallStatisticsModel>();
List<AppCallStatisticsModel> data2 = AppCallStatisticService.GetConnectRatePcInfo(searchModel);
List<AppCallStatisticsModel> data1 = AppCallStatisticService.GetConnectRateAppInfo(searchModel);
data3.AddRange(data2);
data3.AddRange(data1);
var query = from t in data3
group t by t.SearchDate into g
select new AppCallStatisticsModel()
{
SearchDate = g.Key,
SeatCallPercent =g.Sum(c=>ConvertHelper.ToDecimal(c.SeatCallPercent)).ToString("0.00"),
APPCallPercent = g.Sum(c=>ConvertHelper.ToDecimal(c.APPCallPercent)).ToString("0.00")
};