如何找到没有未来日期的最大日期

Question

我正在尝试列出表中每个代码的最新数量(MAX EffectiveDate时间避免Futuristic EffectiveDate)

Code     Quantity EffectiveDate
1        2        1-Mar-2018
1        3        1-Apr-2018
1        3        1-May-2018
1        3        1-June-2018
2        5        1-Mar-2018
2        6        1-Apr-2018
3        7        1-Feb-2018
3        8        1-Mar-2018
3        5        1-Apr-2018

期望的输出应该是:

Code     Quantity EffectiveDate
1        3        1-May-2018
2        6        1-Apr-2018
3        5        1-Apr-2018

我尝试使用MAX BY(DATE)的GROUP BY解决方案, 但它显示了未来数据.

Answer 1

要获得完整的行,您可以使用:

SELECT TOP 1 WITH TIES *
FROM table
WHERE EffectiveDate <= GETDATE()
ORDER BY ROW_NUMBER() OVER(PARTITION BY code ORDER BY EffectiveDate DESC);

DBFiddle演示

编辑:

如果一个代码组中的关系是可能的,那么您可以使用RANK:

SELECT TOP 1 WITH TIES *
FROM tab
WHERE EffectiveDate <= GETDATE()
ORDER BY RANK() OVER(PARTITION BY code ORDER BY EffectiveDate DESC);

DBFiddle演示2