pagination_scope.rb

scope :page, lambda { |number|
    per_page = 2
    limit(per_page).offset(per_page * ([number.to_i, 1].max - 1))
  } do
    def per(number)
      limit(number).offset(offset_value / limit_value * number)
    end

    def num_pages
      (except(:offset, :limit).count.to_f / limit_value).ceil
    end

    def current_page
      offset_value / limit_value + 1
    end
  end