mysql - 如何在 MySQL 中将分组的行连接为单行？

Question

我有一个类似SELECT CONCAT(manufacturer, ':', COUNT(*)) AS count FROM cars GROUP BY manufacturer返回的查询：

+---------+
| count   |
+---------+
| ford:10 |
| fiat:5  |
| kia:2   |
+---------+

现在我想将这些行 GROUP_CONCAT 分成 1 行，例如：

+------------------------+
| result                 |
+------------------------+
| ford:10, fiat:5, kia:2 |
+------------------------+

但是已经有 GROUP BY，所以 GROUP_CONCAT 不起作用。如何使用 MySQL 实现这一点？

Answer 1

select Group_Concat(count SEPERATOR ',') from 
(SELECT CONCAT(manufacturer, ':', COUNT(*)) AS count
 FROM cars GROUP BY manufacturer) AS A