SQL按时间间隔查询

Question

所以我用了this作为引用发布，但我想根据 15 分钟的时间段计算所有行。

这是我目前所拥有的:

SELECT      DateAdd(minute, DateDiff(minute, 0, [datetime]), 0) as Timestamp, 
            Count(*) as Tasks
FROM        [table]
GROUP BY    DateAdd(minute, DateDiff(minute, 0, [datetime]), 0)
ORDER BY    Timestamp

这非常适合每分钟获取行数，但是我需要 15 分钟... 所以我改变:

DateAdd(分钟, DateDiff(分钟, 0, [日期时间]), 0)

到

DateAdd(分钟, DateDiff(分钟, 0, [datetime]), 15)

然而，这只是将日期提前了 15 天。

感谢任何帮助!

Answer 1

要得到 15 分钟，除以 15(然后再乘以):

SELECT      DateAdd(minute, 15*(DateDiff(minute, 0, [datetime]) / 15), 0
                   ) as Timestamp, 
            Count(*) as Tasks
FROM        [table]
GROUP BY    (DateDiff(minute, 0, [datetime]) / 15)
ORDER BY    Timestamp;

SQL Server 进行整数除法。如果您想明确表达自己的意图，请使用 FLOOR()。