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Ruby on rails 处理即时加载和未保存的关联记录_Ruby On Rails_Ruby On Rails 4_Rails Activerecord_Eager Loading - Fatal编程技术网

Ruby on rails 处理即时加载和未保存的关联记录

Ruby on rails 处理即时加载和未保存的关联记录,ruby-on-rails,ruby-on-rails-4,rails-activerecord,eager-loading,Ruby On Rails,Ruby On Rails 4,Rails Activerecord,Eager Loading,如何处理关联记录可能无法保存到数据库的情况 如果我有 class Blog < ActiveRecord::Base has_many :posts end class Post < ActiveRecord::Base has_many :comments end 我可以省略includes语句,但是如果我的代码与评论交互,并且博客和帖子被保存,那就意味着代码会变慢 我使用的是Rails 4.1 blog = Blog.new blog.posts << P

如何处理关联记录可能无法保存到数据库的情况

如果我有

class Blog < ActiveRecord::Base
  has_many :posts
end

class Post < ActiveRecord::Base
  has_many :comments
end
我可以省略
includes
语句,但是如果我的代码与评论交互,并且博客和帖子被保存,那就意味着代码会变慢

我使用的是Rails 4.1

blog = Blog.new
blog.posts << Post.new
blog.posts # => Return value contains one post
blog.posts.includes(:comments) # => Empty result