Question

我的数据如下：

Table
Group: "A" , Color: "Blue", Count: "400"
Group: "A" , Color: "Green", Count: "3"
Group: "A" , Color: "Yellow", Count: "6"
Group: "A" , Color: "Red", Count: "1"
Group: "B" , Color: "Purple", Count: "243"
Group: "B" , Color: "Green", Count: "2"
Group: "B" , Color: "Yellow", Count: "7"

如何查询此数据以获得最受欢迎（按计数）颜色的每个组。所以结果看起来像这样：

Result
Group: "A", Color: "Blue"
Group: "B", Color: "Purple"

Answer 1

SELECT Group, Color
FROM MyTable t
INNER JOIN (SELECT Group, Max(CAST(Count as int)) as Ct
            FROM MyTable
            GROUP BY Group) Sub
   ON sub.group = t.group
   AND sub.ct = t.count

另外，请勿指定字段GROUP或COUNT。它们是关键词，会导致头痛和心碎。

Answer 2

这也应该有效：

SELECT    t.Group,
          t.Color,
          t.Count
FROM     (SELECT   Group,
                   Color,
                   Count,
                   ROW_NUMBER() OVER(PARTITION BY Group ORDER BY CAST(Count AS INT) DESC) AS num
          FROM Table) AS t
WHERE     t.num = 1

抓住每组中最高值的行？

2 个答案: