获取每个组中值最高的行?

I have data that looks like this:

我的数据是这样的:

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"

How can I query this data to get for each group the most popular (by count) color. So the result would look like this:

如何查询此数据以获取每个组最流行(按计数)的颜色。结果是这样的

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

2 个解决方案

#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

As an aside, don't name a field GROUP, or COUNT. They are keywords and will lead to headaches and heartbreak.

顺便说一句，不要命名字段组或计数。它们是关键词，会导致头痛和心碎。

#2

This should also work:

这也应该工作:

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

#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