Question

i have Author entity which belongs_to User. User has_many posts. Please advice how can i show recent_posts on Author entity from User.

class User < ActiveRecord::Base
  has_many :posts, :foreign_key => "author_id"
end

class Post < ActiveRecord::Base
  attr_accessible :title, :content
  belongs_to :author, :class_name => "User"
end

class Author < ActiveRecord::Base
  belongs_to :user
  has_many :recent_posts, :through => :user,
          :class_name => "Post",
          :limit => 3,
          :order => "updated_at desc"
end

How recent_post should be done? Raw sql?

Answer 1

You want the :source option to has_many, which you use to specify the association on the other model, like so:

has_many :recent_posts, :through => :user, :source => :posts, :limit => 3, :order => 'updated_at desc'