Rails，ActiveRecord_Associations_CollectionProxy调用ActiveRecord方法的方式

Question

Board & BoardThread model

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

And I want to use 'select_with_likes' from ActiveRecord_Associations_CollectionProxy class like below.

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

What is awesome way to work this?

Answer 1

You can move the logic into a 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

Slight change to the code is to add the self keyword to your method like so:

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