SQL 将左侧的行组合成一个

Question

当我将多行合并为一行时，我尝试使用左连接创建查询。我尝试使用 GROUP_CONTENT 函数，但是当我尝试使用它时，我的数据库服务器出现故障。我使用 MariaDB 10.3.17。我有这样的表：

游戏：

game_id game_name
1       Test
2       Stack
3       Other

data_developers:

dev_id dev_name
1      Electronic Arts
2      BioWare
3      2K Games

game_developers

developer_id game_id
1            1
2            1
2            3

我想要的结果：

game_id game_name devs
1       Test      Electonics Arts, BioWare
2       Stack     2K Games

我的两个 sql（但没用）

SELECT games.*, GROUP_CONCAT(data_developers.dev_name) 
FROM games 
LEFT JOIN game_developers ON game_developers.game_id = games.game_id
LEFT JOIN data_developers ON data_developers.dev_id = game_developers.dev_id
LIMIT 500

和第二个查询

SELECT games.*
FROM games
LEFT JOIN game_developers ON game_developers.game_id = games.game_id
LEFT JOIN 
(SELECT GROUP_CONCAT(data_developers.developer_name) as developers, 
data_developers.developer_id FROM data_developers) x 
ON x.developer_id = game_developers.developer_id

当然，也行不通:(

Answer 1

您的查询应该如下所示-

SELECT A.game_id,B.Game_name,GROUP_CONCAT(C.dev_name)
FROM game_developers A
INNER JOIN Games B ON A.game_id = B.game_id
INNER JOIN data_developers C ON A.developer_id = C.dev_id
GROUP BY A.game_id,B.Game_name

SQL 将左侧的行组合成一个

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mariadb

mariadb-10.3