Apache pig 连接两个关系（候选人）并显示选票之间的差异？

我首先把这种关系分为赢的和输的

我很难将所有候选人重新组合在一起，并将两位候选人（当选和落选）的姓氏和选票总数之间的差值（只有差值小于10的元组）组成元组

为了显示不同点，顺便说一句，这是我的想法，但它不起作用：

jnd = JOIN won BY lastname AS lastname_won, vote AS vote_won, lost BY lastname AS lastname_lost, vote AS vote_lost;

gen = foreach jnd generate lastname_won, lastname_lost,(vote_won - vote_lost) as diffVotes; 

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到底是什么不起作用

乍一看，您的加入可能无法工作，因为您正在使用。无法重命名联接中的列，为此需要foreach。使用：：区分两个关系中的字段：

jnd2 = FOREACH jnd GENERATE won::lastname AS lastname_won, won::vote AS vote_won etc.

如果在多个列上联接，请按以下方式更改语法：

jnd = JOIN won BY (lastname, vote), lost BY (lastname, vote);

jnd = JOIN won BY (lastname, vote), lost BY (lastname, vote);