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Ruby on rails 如何调用ActiveRecord::Result上的关联_Ruby On Rails_Ruby On Rails 5_Rails Activerecord - Fatal编程技术网

Ruby on rails 如何调用ActiveRecord::Result上的关联

Ruby on rails 如何调用ActiveRecord::Result上的关联,ruby-on-rails,ruby-on-rails-5,rails-activerecord,Ruby On Rails,Ruby On Rails 5,Rails Activerecord,我有两种型号City和State。下面是城市和州之间的联系 state.rb has_many :cities city.rb belongs_to :state 我执行了下面的查询 connection = ActiveRecord::Base.connection query = "select * from states" @states = connection.exec_query(query); 现在我重复一遍 @states.each do |s| s.cities #

我有两种型号
City
State
。下面是城市和州之间的联系

state.rb

has_many :cities
city.rb

belongs_to :state
我执行了下面的查询

connection = ActiveRecord::Base.connection
query = "select * from states"
@states = connection.exec_query(query);
现在我重复一遍

@states.each do |s|
  s.cities # gives me an error because it is not an state object
end 
我想要它像

state = State.last

cities = state.cities

如何在使用循环对其进行迭代时使用
@states
执行此操作?

您将希望使用如下ActiveRecord关联:

State.all.each { |state| state.cities }

它应该是
query=“select*from states”
很抱歉,它已经是states了。假设您不想实例化实际的模型对象?请发布针对
@states
的准确错误日志和结果类/查询。