whatevz.rb

require 'active_record'
ActiveRecord::Base.establish_connection adapter: 'sqlite3', database: ':memory:'
ActiveRecord::Schema.define do
  self.verbose = false
  create_table :businesses do |t|
    t.string :name
  end
  create_table :orders do |t|
    t.string  :name
    t.integer :business_id
    t.integer :status_id
  end
end

class Business < ActiveRecord::Base
  has_many :orders
end

class Order < ActiveRecord::Base
  belongs_to :business
  scope :ordered,   -> { where status_id: 1 }
  scope :cancelled, -> { where status_id: 2 }
end

Business.create! name: 'Turing' do |b|
  b.orders.build name: 'books',     status_id: 1
  b.orders.build name: 'computers', status_id: 2
  b.orders.build name: 'tables',    status_id: 1
  b.orders.build name: 'chairs',    status_id: 3
end

class OrdersPresenter
  def initialize(all_orders)
    @all_orders = all_orders
  end
  def ordered
    @all_orders.where(status_id: 1)
  end
  def ordered_names
    ordered.map(&:name)
  end
  def cancelled
    @all_orders.where(status_id: 2)
  end
end

# setup
business = Business.first

# no abstractions
orders   = business.orders
orders.where(status_id: 1).map(&:name)
orders.where(status_id: 2).map(&:name)

# presenter solution
orders = OrdersPresenter.new(business.orders)
orders.ordered_names
orders.cancelled.map(&:name)

# scope solution
orders = business.orders
orders.ordered.map(&:name)
orders.cancelled.map(&:name)