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Ruby on rails Rails Activerecord反向关联_Ruby On Rails_Ruby On Rails 3_Activerecord - Fatal编程技术网
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Ruby on rails Rails Activerecord反向关联

ruby-on-rails ruby-on-rails-3 activerecord

Ruby on rails Rails Activerecord反向关联,ruby-on-rails,ruby-on-rails-3,activerecord,Ruby On Rails,Ruby On Rails 3,Activerecord,我有模型： class Materialtitle < ActiveRecord::Base has_many :edocs end class Edoc < ActiveRecord::Base belongs_to :materialtitles end class Materialtitle

我有模型：

class Materialtitle < ActiveRecord::Base
  has_many :edocs
end

class Edoc < ActiveRecord::Base
     belongs_to :materialtitles
end

class Materialtitle
我可以做
Materialtitle.find（2）.edocs

我想做一些类似于
Edoc.find（10）.materialtitles
的事情。但它返回nil

有人能帮我吗？

如果它是多对一，那么它应该是
属于：materialtitle
（单数），并且您的DSL应该是：

 Edoc.includes(:materialtitle).find(10).materialtitle