cheat sheets.

AT notes:
# Add to existing model
$ rails generate migration AddStaticDataJSONToReports static_data_json:string
$ vim db/migrate/20120209232000_add_static_data_json_to_reports.rb 
+ "add_column :reports, :static_data_json, :text, :limit => 4294967295"
$ bundle exec rake db:migrate
# Create a new model
$ rails generate model GhostApplication application_name:string
application_label:string file_hash:string  file_hash_sha1:string
file_hash_sha256:string platform:integer requests:integer



http://wiki.rubyonrails.com/rails/pages/UsingMigrations

valid data types:
  :integer :float
  :datetime :date :timestamp :time
  :text :string
  :binary
  :boolean
options:
  :null (boolean)
  :limit (integer)
  :default
  :precision (integer)
  :scale (integer)

create the model       ./script/generate model model_name
apply schema changes   rake db:migrate
modify schema          ./script generate migration description_name