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简而言之：在 MSSQL 2005 中使用 WITH CUBE 时，有没有办法直接计算中值，最好不使用循环？

一些代码：

CREATE TABLE #Example (
    ID1 INT,
    ID2 INT,
    [Value] INT
)

INSERT #Example(ID1,ID2,[Value])
    SELECT 1, 1, 45 UNION
    SELECT 1, 2, 78 UNION
    SELECT 1, 3, 23 UNION
    SELECT 1, 4, 119 UNION
    SELECT 1, 5, 85 UNION
    SELECT 2, 1, 143 UNION
    SELECT 2, 2, 124 UNION
    SELECT 2, 3, 161 UNION
    SELECT 2, 4, 171 UNION
    SELECT 2, 5, 142

SELECT ID1, ID2, COUNT(1) AS 'NumValues', MIN([Value]) AS 'Minimum', AVG([Value]) AS 'Average', MAX([Value]) AS 'Maximum'
    FROM #Example
    GROUP BY ID1, ID2
    WITH CUBE
    HAVING ID1 IS NULL OR ID2 IS NULL
    ORDER BY ISNULL(ID1, 0), ISNULL(ID2, 0)

DROP TABLE #Example

如何获得中值的列？

到目前为止，我管理的最好方法是遍历 ID1 和 ID2 值，并计算每组 ID 的中值，但这似乎效率低下且丑陋。

任何想法都感激不尽！

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1 回答 1

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Somewhat belatedly, I think that this would work:

select * from
(
    SELECT ID1, ID2, COUNT(1) AS 'NumValues', MIN([Value]) AS 'Minimum', AVG([Value]) AS 'Average', MAX([Value]) AS 'Maximum'
    FROM #Example
    GROUP BY ID1, ID2
    WITH CUBE
    HAVING ID1 IS NULL OR ID2 IS NULL
) T
OUTER APPLY 
(
    select avg(val) as median from
    (
        select [value] as val, row_number() over (order by [value]) as rn
        from #Example E 
        where (T.ID1=E.ID1 or T.ID1 is null) and (T.ID2=E.ID2 or T.ID2 is null) 
    ) I
    where abs(rn - (T.NumValues+1)/2.0) <1
) T2
于 2011-06-17T12:16:38.707 回答