sqlserver 按日分组

--根据日期字段AddTime，得到每日的数据量
SELECT
  CAST(AddTime AS DATE) AS riqi, COUNT(*) AS TotalOrders
FROM
  MoJingKaKouRecord
GROUP BY
  CAST(AddTime AS DATE)
  order by riqi desc

--统计出每日的车牌数量（同一个车牌，同一天只算一次）
select riqi,count(*) as num from 
(
SELECT
  CAST(AddTime AS DATE) AS riqi, COUNT(*) AS TotalOrders
FROM
  MoJingKaKouRecord
  GROUP BY
  CAST(AddTime AS DATE),PlateNo
  ) as t1
  group by riqi
  order by riqi desc

--指定时间范围内的车牌总数（每个车牌每日只统计一次）
select sum(num) from
(
		select riqi,count(*) as num from 
		(
				SELECT
				  CAST(AddTime AS DATE) AS riqi, COUNT(*) AS num
				FROM
				  MoJingKaKouRecord
				GROUP BY
				  CAST(AddTime AS DATE),PlateNo
		  ) as t1
		  group by riqi
  ) as t2
  where riqi >='2024-9-1'  and riqi <'2024-10-1'