gistfile1.txt

(1..143671).step(100) do |n|
  puts "working on block #{n}"
  Subscriber.find(:all, :conditions => ["id between ? and ?", n, n+100], :limit => 100).each do |s|
    next unless s.card_number
    if ['8714', '0436', '0704', '4008'].include?(s.card_number[-4,4])
      puts "#{s.id} #{s.card_number}"
    end
  end
end