轨道范围3的ActiveRecord立即加载 [英] Rails 3 ActiveRecord eager loading of scope

问题描述

请帮助我。 我有一些模式，HAS_MANY与其他模型关联。 例如：配置=>的has_many：统计 和统计模型中，我有一些范围：

Help me please. I have some model which has_many association with other model. For example: profile => has_many :statistics And inside of statistic model I have some scope:

scope last_ten, limit(10).order('online desc')

和问题是我怎么可以用贪婪加载这个范围是什么？我不需要统计分布的每个记录。只有作用域。

And question is how can I use eager load for this scope? I don't need every record of statistics for profile. Only scoped.

现在我只能用

 User.profiles.includes(:statistics)

感谢。

推荐答案

按如下说明：<一href="http://api.rubyonrails.org/classes/ActiveRecord/Associations/ClassMethods.html">http://api.rubyonrails.org/classes/ActiveRecord/Associations/ClassMethods.html

这是更好地定义自定义关系：

It's better to define a custom relation:

class Profile < ActiveRecord::Base
  has_many :most_recent_stats, :class_name => 'Statistic', :order => 'online DESC', :limit => 10
  ...
end

User.profiles.includes(:most_recent_stats)

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