通过检索3个值组

Question

我有以下查询

SELECT  Cod ,
        MIN(Id) AS id_Min,
        MAX(Id) AS id_Max,
        -- retrieve value in the middle,
        COUNT(*) AS Tot

FROM    Table a ( NOLOCK )        
GROUP BY Cod
HAVING  COUNT(*)=3

我怎样才能在最小值和最大值之间检索值，就像我为min和max做的那样？

实施例

Cod      |  Id

Stack       10
Stack       15
Stack       11
Overflow    100
Overflow    120
Overflow    15

必需的输出

Cod         | Min   | Value_In_The_Middle  |    Max

Stack         10          11                    15
Overflow      15          100                   120

Answer 1

我没有对此进行过测试，但我认为这样可行

SELECT  Cod ,
        MIN(Id) AS id__Min,
        MAX(Id) AS id_Max,
        SUM(ID)-MAX(Id)-MIN(Id) as id_Middle,
        COUNT(*) AS Tot
FROM    Table a ( NOLOCK )        
GROUP BY Cod
HAVING  COUNT(*)=3

只有当你有3个值并且SUM（）没有溢出时（例如Bogdan Sahlean在评论中指出），这个技巧才有效。