Question

我有3张桌子，

 user { id, name, email }
 games { id, name, icon } 
 user_games {id_user, id_game}

我想选择用户没有的游戏。

这是我最好的尝试，但什么都不返回。但最后不要给出错误信息XD

SELECT a.* 
FROM games a 
LEFT JOIN user_games b ON a.id IN (b.id_game) AND '1' IN (b.id_user) 
WHERE (b.id_game IS NULL) AND b.id_user <> '1'

请帮忙。

Answer 1

看起来你大多拥有它。最后的user_games.id_user＆lt;＆gt; 1可能不是您想要的，因为您正在查找id_user为null且null＆lt;＆gt; 1的情况也为空。

SELECT games.*
FROM games
   LEFT JOIN user_games on (
       games.id = user_games.id_game AND
       user_games.id_user = '1'
   )
WHERE user_games.id_user IS NULL

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