MySQL 中执行的子查询

Question

我是运行下面的查询

(
  select Game.GameID, Game.season, GamePlaysPlayers.playerID
  from (select Game.GameID, Game.season, GamePlaysPlayers.playerID
        from Game 
        inner join GamePlaysPlayers on Game.GameID = GamePlaysPlayers.GameID 
        where Game.season = '20082009'
       )
  inner join (
    select Game.GameID, Game.season, GamePlaysPlayers.playerID 
    from Game 
    inner join GamePlaysPlayers on Game.GameID = GamePlaysPlayers.GameID 
    where Game.season = '20182019'
  ) on Game.GameID = GamePlaysPlayers.GameID
);

我收到错误消息“每个派生的 table 都必须有自己的别名”。

Answer 1

错误信息很清楚。如果您参考 MySQL 文档 https://dev.mysql.com/doc/refman/8.0/en/derived-tables.html，每个派生的 table 的名称是强制性的，因此您必须在两个子查询中包含一个 AS 子句。我猜第一个子查询的名称是“Game”，第二个子查询的名称是“GamePlaysPlayers”。

MySQL 中执行的子查询

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