我组织严密的表格的另一个问题

Question

我有一个像这样的表设置:

fruit1 | fruit2 | fruit3 | fruit4 | number1 | number2 | number3 | number4
--------------------------------------------------------------------------
apple  | orange | banana |  berry |    5    |    2    |    1    |    4   
orange | banana | apple  |  berry |    3    |    2    |    5    |    2
berry  | banana | orange |  apple |    1    |    2    |    5    |    2

我需要一个MySQL查询来计算每个水果每个数字的次数.所以,它最终会是这样的:

Fruit | 5's | 4's | 3's | 2's | 1's 
-----------------------------------
Apple | 2   | 0   | 0   | 1   | 0 
Banana| 0   | 0   | 1   | 1   | 1
...

JW帮我解决了很多问题,但我无法弄清楚如何从JW的解决方案转向我现在需要的解决方案.
需要帮助搞清楚MySQL查询是否计算一定数量

Answer 1

由于您在评论中已经提到最大值为5,所以这里是一个旋转版本,使用case您之前想要的问题,

SELECT fruit,
       SUM(CASE WHEN num = 5 THEN NumberOfInstance ELSE 0 END) `5's`,
       SUM(CASE WHEN num = 4 THEN NumberOfInstance ELSE 0 END) `4's`,
       SUM(CASE WHEN num = 3 THEN NumberOfInstance ELSE 0 END) `3's`,
       SUM(CASE WHEN num = 2 THEN NumberOfInstance ELSE 0 END) `2's`,
       SUM(CASE WHEN num = 1 THEN NumberOfInstance ELSE 0 END) `1's`
FROM
      (
        SELECT fruit, num, COUNT(*) NumberOfInstance
        FROM 
        (
          SELECT fruit1 fruit, number1 num FROM table1
          UNION ALL
          SELECT fruit2 fruit, number2 num FROM table1
          UNION ALL
          SELECT fruit3 fruit, number3 num FROM table1
          UNION ALL
          SELECT fruit4 fruit, number4 num FROM table1
        ) s 
        GROUP BY fruit, num
      ) s
GROUP BY fruit;

• SQLFiddle演示链接