Question

我有以下mysql-table cars布局

BRAND   | TYPE  | COLOR
-----------------------
bmw     | e30   | red
bmw     | e90   | blue
bmw     | e12   | red
audi    | a3    | green
bmw     | e90   | red
audi    | tt    | blue
bmw     | e12   | blue
audi    | a3    | green

并希望通过以下布局获得数据透视表：

brand_type  | red   | blue  | green | total 
-------------------------------------------
bmw-e30     | 1     | 0     | 0     | 1
bmw-e90     | 1     | 1     | 0     | 2
bmw-e12     | 1     | 1     | 0     | 2
audi-a3     | 0     | 0     | 2     | 2
audi-tt     | 0     | 1     | 1     | 2

我能做到的最重要的是这个问题：

SELECT brand, 
    sum(if(color = 'red', 1, 0)) as red, 
    sum(if(color = 'blue', 1, 0)) as blue, 
    sum(if(color = 'green', 1,0)) as green,
    count(color) as total
FROM `cars` group by brand;

结果如下：

brand   | red   | blue  | green | total 
-------------------------------------------
bmw     | 3     | 2     | 0     | 5
audi    | 0     | 1     | 3     | 4

我已经在网上搜索了，但我找不到任何解决方案，其中2列（品牌和类型）已合并枢轴结果中使用 AND

1。我怎样才能获得所需的数据透视表结果？解决@kevinsjöberg的暗示

SELECT concat(brand, '-', type) as BT, 
    sum(if(color = 'red', 1, 0)) as red, 
    sum(if(color = 'blue', 1, 0)) as blue, 
    sum(if(color = 'green', 1,0)) as green,
    count(color) as total
FROM `cars` group by BT;

[删除了第二个问题，因为它已经用第一个答案解决了]

Answer 1

使用MySQL的CONCAT功能。

CONCAT(`BRAND`, '-', `TYPE`)

您然后GROUP BY brand和type。

请参阅http://sqlfiddle.com/#!9/6d3db/2

mysql数据透视表，包含所选行的concat和pivot计数

1 个答案: