has_one :original_license
has_one :common_license
validates :name, :presence => true, :length => {:maximum => 50}
- validates :url, :presence => true, :length => {:maximum => 200}, :uniqueness => true
+ validates :url, :presence => true, :length => {:maximum => 200}, :uniqueness => true, :url => {:allow_blank => true}
def self.update_license cl
l = License.find_by_url cl.url