Owned Sites

user.rb

class User < ApplicationRecord
  has_many :site_users, dependent: :destroy
  has_many :sites, through: :site_users

  def owned_sites
    sites.where("site_users.roles_mask = ?", SiteUser.mask_for(:owner))
  end

  def owned_sites_using_includes
    sites.includes(:site_users).where("site_users.roles_mask = ?",SiteUser.mask_for(:owner))
  end
end

zoutput.irb

irb(main):003:0> User.first.owned_sites.all
  User Load (0.2ms)  SELECT  "users".* FROM "users" ORDER BY "users"."id" ASC LIMIT ?  [["LIMIT", 1]]
  Site Load (0.2ms)  SELECT  "sites".* FROM "sites" INNER JOIN "site_users" ON "sites"."id" = "site_users"."site_id" WHERE "site_users"."user_id" = ? AND (site_users.roles_mask = 16) LIMIT ?  [["user_id", 1], ["LIMIT", 11]]
=> #<ActiveRecord::AssociationRelation [#<Site id: 1, name: "ok", created_at: "2019-04-02 18:40:23", updated_at: "2019-04-02 18:40:23">]>
irb(main):004:0> User.first.owned_sites_using_includes.all
  User Load (0.1ms)  SELECT  "users".* FROM "users" ORDER BY "users"."id" ASC LIMIT ?  [["LIMIT", 1]]
  Site Load (0.1ms)  SELECT  "sites".* FROM "sites" INNER JOIN "site_users" ON "sites"."id" = "site_users"."site_id" WHERE "site_users"."user_id" = ? AND (site_users.roles_mask = 16) LIMIT ?  [["user_id", 1], ["LIMIT", 11]]
  SiteUser Load (0.1ms)  SELECT "site_users".* FROM "site_users" WHERE "site_users"."site_id" = ?  [["site_id", 1]]
=> #<ActiveRecord::AssociationRelation [#<Site id: 1, name: "ok", created_at: "2019-04-02 18:40:23", updated_at: "2019-04-02 18:40:23">]>