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Rails 3 Automatically create join tables

I find it difficult to understand how to create new records in a table and automatically create related relationships in a joined table.

Here are my models:

class Building < ActiveRecord::Base
  has_many :user_buildings
  has_many :users, :through => :user_buildings
end

class User < ActiveRecord::Base
  has_many :user_buildings
  has_many :buildings, :through => :user_buildings
  ....
end

class UserBuilding < ActiveRecord::Base
  belongs_to :user
  belongs_to :building
end

Now my user model is also used for development, so I use the current_user helper.

To get all the buildings that I use

current_user.buildings

So, from there I thought I could use

current_user.buildings.build

create a new building associated with the user and update the joined table; however, this adds the building to the building table and does not make an association in the user_buildings table.

I read the documentation at http://api.rubyonrails.org/classes/ActiveRecord/Associations/ClassMethods.html , but I cannot figure out which direction I need to go.

Thank!

+3
1

, .

current_user.buildings << Building.new(:some_building_attributes => :some_value)
current_user.save
+1

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