razi@ubuntu:~/image$ rails generate paperclip product photo
      create  db/migrate/20110928133441_add_attachment_photo_to_product.rb
razi@ubuntu:~/image$ rake db:migrate
==  AddAttachmentPhotoToProduct: migrating ====================================
-- add_column(:products, :photo_file_name, :string)
rake aborted!
An error has occurred, this and all later migrations canceled:

SQLite3::SQLException: no such table: products: ALTER TABLE "products" ADD "photo_file_name" varchar(255)

Tasks: TOP => db:migrate
(See full trace by running task with --trace)