Question

我正在尝试将PERCENTILE_DISC与许多其他内置聚合函数一起使用。我尝试的代码是这样写的，但它失败了：

SELECT
    [DataPoint] AS [DataPoint],
    MIN([Value]) AS [Value MIN],
    MAX([Value]) AS [Value MAX],
    AVG([Value]) AS [Value AVG],
    PERCENTILE_DISC(0.5)
        WITHIN GROUP 
        (ORDER BY [Value])
        OVER 
        (PARTITION BY [DataPoint])
        AS MedianCont
    FROM [Table] AS [Table]
    WHERE ([DataPoint]
        IN (
            ...
        )
    )
    GROUP BY [DataPoint]

所以这有效......

SELECT
    Distinct [DataPoint],
    PERCENTILE_DISC(0.5)
    WITHIN GROUP 
    (ORDER BY [Value])
    OVER 
    (PARTITION BY [DataPoint])
    AS MedianCont
    FROM [Table] AS [Table]
    WHERE ([DataPoint]
        IN (
            ...
        )
    )

这有效......

SELECT
    [DataPoint] AS [DataPoint],
    MIN([Value]) AS [Value MIN],
    MAX([Value]) AS [Value MAX],
    AVG([Value]) AS [Value AVG]
    FROM [Table] AS [Table]
    WHERE ([DataPoint]
        IN (
            ...
        )
    )
    GROUP BY [DataPoint]

但是当我尝试将它们组合起来时，它希望我在Value子句中声明Group By，这是我不想要的，因为我想要一个明确的DataPoint列表，不是每DataPoint的值。

Column 'Value' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause.

Answer 1

似乎使用over clause，从而创建了一个＆＃39;窗口函数＆＃39;，将聚合函数与select语句分开。

SELECT
    Distinct [DataPoint],
    MIN([Value]) OVER (PARTITION BY [DataPoint]) AS [Value MIN],
    MAX([Value]) OVER (PARTITION BY [DataPoint]) AS [Value MAX],
    AVG([Value]) OVER (PARTITION BY [DataPoint]) AS [Value AVG],
    PERCENTILE_DISC(0.5)
        WITHIN GROUP 
        (ORDER BY [Value])
        OVER 
        (PARTITION BY [DataPoint])
        AS MedianCont
    FROM [Table] AS [Table]
    WHERE ([DataPoint]
        IN (
            ...
        )
    )

使用具有聚合函数的PERCENTILE_DISC

1 个答案: