Raylar, ActiveRecord_Associations_CollectionProxy ActiveRecord

Question

Kurulu & BoardThread modeli

class Board < ActiveRecord::Base 
    has_many :board_threads 
end 

class BoardThread < ActiveRecord::Base 
    belongs_to :board 
    has_many :likes, as: :likable 

    def select_with_likes 
     select("*, (SELECT COUNT(likes.id) FROM likes WHERE likable_id = board_threads.id AND likable_type = 'BoardThread') AS likes_cnt") 
    end 
end 

yöntemi çağırmak Ve aşağıda gibi ActiveRecord_Associations_CollectionProxy sınıfından 'select_with_likes' kullanmak istediğiniz için yol.

b = Board.first 
b.board_threads.select_with_likes.order()... 

Bunun için harika bir yol nedir?

Answer 1

Sen koduna scope

class BoardThread < ActiveRecord::Base 
    belongs_to :board 
    has_many :likes, as: :likable 

    scope :with_likes, -> { 
     select("*, (SELECT COUNT(likes.id) FROM likes WHERE likable_id = board_threads.id AND likable_type = 'BoardThread') AS likes_cnt") 
    } 
end 

board_threads = Board.first.board_threads.with_likes.order(...) 

Answer 2

hafif değişim içine mantığı hareket böylece gibi yöntemine kendine anahtar kelime eklemektir:

def self.select_with_likes 
    select("*, (SELECT COUNT(likes.id) FROM likes WHERE likable_id = board_threads.id AND likable_type = 'BoardThread') AS likes_cnt") 
end