Question

给出这个样本数据集：

Date_Time
10/1/2011 12:05:00 AM
10/6/2011 2:25:00 AM
10/3/2011 5:59:00 AM
10/19/2011 6:01:00 PM
11/5/2011 8:30:00 PM
11/30/2011 11:59:00 PM

SQL Server（2005或2008）中是否有可以计算这两个时间范围内记录数的日期时间函数？以下是上述数据集的结果。如果一个网站也显示这个，请告诉我。非常感谢，伙计们。

Midnight-6:00am     6:00pm – Midnight. 
3                   3

Answer 1

注意，您希望第二个范围到达晚上11:59，而不是午夜...使用DATEPART()获取日期的小时部分并使用汇总SUM()添加1达到每个范围的总数。所以你需要的是0到5（00:00 - 05:59）和18和23（18:00 - 23:59）之间的小时

SELECT
  SUM(CASE WHEN DATEPART(hour, Date_Time) BETWEEN 0 AND 5 THEN 1 ELSE 0 END) AS  [Midnight to 6:00am],
  SUM(CASE WHEN DATEPART(hour, Date_Time) BETWEEN 18 AND 23 THEN 1 ELSE 0 END) AS  [6:00pm to 11:59pm]
FROM your_table

更新

以上计算时间为05:59:59 am。如果这真的应该计算到06:00:00，您还需要检查6:00的各个时间部分。这可能很慢。

SELECT
  SUM(CASE WHEN
        DATEPART(hour, Date_Time) BETWEEN 0 AND 5 
        -- Look for 06:00:00 by stripping off the date portion and comparing against a character string
        OR (DATEPART(hour, Date_Time) = 6 AND DATEPART(minute, Date_Time) = 0 AND DATEPART(second, Date_Time) = 0)
      THEN 1 ELSE 0
      END
  ) AS [Midnight to 6:00am],
SUM(CASE WHEN DATEPART(hour, Date_Time) BETWEEN 18 AND 23 THEN 1 ELSE 0 END) AS  [6:00pm to 11:59pm]
FROM your_table

或者，使用

可能会更快

  SUM(CASE WHEN
        DATEPART(hour, Date_Time) BETWEEN 0 AND 5 
        -- Look for 06:00:00 also
        OR CONVERT(VARCHAR, Date_Time, 108) = '06:00:00'
      THEN 1 ELSE 0
      END
  ) AS [Midnight to 6:00am],

在SQL中计算AM和PM

1 个答案:

更新