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MySQL语句转换为漂亮的Rails AR语句?
原标题:MySQL statement convert to pretty Rails AR Statement?

我有一个MySQL语句,花了我一晚上的时间才想出。我想知道这个东西是否可以从直接调用转换为类似Object.find(:conditions)的东西

    ActiveRecord::Base.connection.execute("
    SELECT *, 
      (SELECT COUNT(*) 
      FROM scores AS temp2 
      WHERE temp2.score > scores.score 
      ORDER BY score DESC) + 1 AS rank 
    FROM scores 
    WHERE user_id=%s 
    ORDER BY score DESC" 
    % user_id).fetch_hash

这个声明是为安卓游戏构建的高分网站的一部分。它获得了最高的高分,并且有一个子查询也为它提供了排名。

这个可以做得更好吗?此外,这是最有效的方法吗?

Thanks, Justin

最佳回答

这应该为您做到:

user = Score.find_by_user_id(id)
rank = Score.count(:conditions => [ score > ? , user.score]) + 1
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