I have these models:
class Item < ActiveRecord::Base
has_many :item_categoryships
has_many :categories, class_name: 'ItemCategoryship', foreign_key: 'category_id', :through => :item_categoryships
belongs_to :user
validates :title, presence: true
end
class Category < ActiveRecord::Base
has_many :item_categoryships
has_many :items, :through => :item_categoryships
belongs_to :user
validates :name, presence: true
end
class ItemCategoryship < ActiveRecord::Base
belongs_to :item
belongs_to :category
validates :item_id, presence: true
validates :category_id, presence: true
end
class User < ActiveRecord::Base
has_many :items
has_many :categories, class_name: 'Category'
# Include default devise modules. Others available are:
# :confirmable, :lockable, :timeoutable and :omniauthable
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable, :confirmable, :async
end
But I found when I call item.categories will get a empty array !!! I have checked database, there is a record here.
When I test in the rails console, I didn't get any record back, just saw 'ActiveRecord::Associations::CollectionProxy []'.
What is this? I am using Rails 4.0.2.
Thanks you all.
ActiveRecord::Associations::CollectionProxy
is ActiveRecord
class for collection associations. Now, your code should work if you change line in Item
class describing categories
association to:
has_many :categories, through: :item_categoryships
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