## lib/paperclip_processors/laod_file.rb
module Paperclip
  class LoadFile < Processor

    def make
      File.readlines(@file.path).collect(&:chomp).each do |line|
        email, account_number, sub_number, eid, premium_code, keycode, order_date, description = line.split("\t")

        MailingList.new(email => :email, account_number => :account_number, sub_number => :sub_number, eid => :eid,
                        premium_code => :premium_code, keycode => :keycode, order_date => :order_date, description => :description)
      end
    end
  end
end

## app/models/mailing_list.rb
class MailingList < ActiveRecord::Base

  has_attached_file :list_file,
                    :processors => [:load_file]

end