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Mysql Rails ActiveRecord具有多个关联级别_Mysql_Ruby On Rails_Ruby On Rails 3_Activerecord - Fatal编程技术网

Mysql Rails ActiveRecord具有多个关联级别

Mysql Rails ActiveRecord具有多个关联级别,mysql,ruby-on-rails,ruby-on-rails-3,activerecord,Mysql,Ruby On Rails,Ruby On Rails 3,Activerecord,我在查询具有不同关联类型的多个表时遇到了一些问题。有人能给我指一下正确的方向吗 class Sale < ActiveRecord::Base has_many :items, :dependent => :destroy end class Item < ActiveRecord::Base belongs_to :sale, :dependent => :destroy has_many :images, :dependent => :dest

我在查询具有不同关联类型的多个表时遇到了一些问题。有人能给我指一下正确的方向吗

class Sale < ActiveRecord::Base
    has_many :items, :dependent => :destroy
end

class Item < ActiveRecord::Base
  belongs_to :sale, :dependent => :destroy
  has_many :images, :dependent => :destroy
end

class Image < ActiveRecord::Base
  belongs_to :item, :dependent => :destroy
end
class Sale:销毁
结束
类项:destroy
有许多:映像,:依赖=>:销毁
结束
类映像:销毁
结束
要获取与ID为1的销售相关的所有项目,然后遍历与返回的每个项目相关的所有图像,该查询是什么


谢谢你的帮助。

你可以定义
:通过=>:一个
中的某个
有很多关联

class Sale < ActiveRecord::Base
    has_many :items, :dependent => :destroy
    has_many :images, :through => :items
end

它会出现一些问题,因为它不会返回与当前处于循环中的项目相关的图像(请参见下面的代码)
销售中的项目0%>

Title:

此销售中没有项目收听

还有什么想法吗?
Sale.find(1).images