Question

希望你能帮助我！

我有以下数据库：

country | Date_of_birth
-----------------------
france  | 1980-07-01
spain   | 1978-03-23
greece  | 1981-05-05
germany | 1974-08-11

我正试图得到这个结果：

country | 13 - 17 | 25 - 45 | 65 - 75
-------------------------------------
france  |         |     1   |
spain   |         |     1   |
greece  |         |     1   |

查询我发现了这一点：

SELECT SUM( IF( age BETWEEN 13 AND 17 , 1, 0)) AS '13 - 17', 
       SUM( IF( age BETWEEN 25 AND 45 , 1, 0)) AS '25 - 45', 
       SUM( IF( age BETWEEN 65 AND 75 , 1, 0)) AS '65 - 75'
FROM (SELECT TIMESTAMPDIFF( YEAR, Date_of_birth, CURDATE()) AS age, country FROM data
) AS test
GROUP BY country
HAVING country IN ("france","greece,"spain")

结果：

 13 - 17 | 25 - 45 | 65 - 75
----------------------------
         |     1   |
         |     1   |
         |     1   |

我知道如何在开始时获得“国家/地区”专栏吗？

提前致谢!!

Answer 1

Having仅适用于聚合列。你想要一个简单的where：

SELECT 
       country,
       SUM(age BETWEEN 13 AND 17) AS '13 - 17', 
       SUM(age BETWEEN 25 AND 45) AS '25 - 45', 
       SUM(age BETWEEN 65 AND 75) AS '65 - 75'
FROM (SELECT TIMESTAMPDIFF( YEAR, Date_of_birth, CURDATE()) AS age, country FROM data
      ) AS test
WHERE country IN ('france', 'greece', 'spain')
GROUP BY country

还要注意查询的简化：在mysql true中1而false是0，所以你可以简单地总结条件 - 你不需要case。

此外，您遇到语法错误 - 您需要在您的国家/地区值附近使用单引号。

Answer 2

如果您想要包含“country”列，则必须将其添加到SELECT部分：

SELECT
   country, 
   SUM( IF( age BETWEEN 13 AND 17 , 1, 0)) AS '13 - 17', 
   SUM( IF( age BETWEEN 25 AND 45 , 1, 0)) AS '25 - 45', 
   SUM( IF( age BETWEEN 65 AND 75 , 1, 0)) AS '65 - 75'
FROM (SELECT TIMESTAMPDIFF( YEAR, Date_of_birth, CURDATE()) AS age, country FROM data
) AS test
GROUP BY country
HAVING country IN ("france","greece,"spain")

Answer 3

SELECT country, SUM...., SUM..., SUM...

sql在年龄组之间

3 个答案: