Question

I’m just wondering if someone could explain to me how to create a relationship (programmatic example would be helpful, so I can test in rails console) between two objects where the relationship is defined as a has_many :through that has additional attributes. The objects are defined as below:

class Item < ActiveRecord::Base
  has_many :collections, :through => :collection_items
end

---

class Collection < ActiveRecord::Base
  has_many :items, :through => :collection_items
end

---

class CollectionItem < ActiveRecord::Base
  belongs_to :collection
  belongs_to :item

  attr_accessible :collection_id, :item_id, :quantity
end

Answer 1

Try this:

CollectionItem.create(item_id: Item.first, collection_id: Collection.first, quantity: 999)

Just replace the ‘Item.first‘ and ‘Collection.first‘ with whatever logic you have to get the right item and collection.