>> @moo.to_s
=> "james cosby-wolf was Zen order 27,\n      so we'll call it number 27."
>> @moo.moocash_orders_id
=> 27
>> @moo.save
ActiveRecord::StatementInvalid: SQLite3::SQLException: SQL logic error or missing database: INSERT INTO "moocash_orders" ("moocash_orders_id", ... "created_at") VALUES(NULL, ... NULL, '2008-11-06 17:40:30', '2008-11-06 17:40:30')

class MoocashOrder < ActiveRecord::Base
attr_reader :student_fname, :moocash_orders_id

##stuff

  def to_s
    string = "#{@student_fname} #{@student_lname} was Zen order #{@moocash_orders_id},"
      + " so we'll call it number #{@moocash_id}."
  end

end