In my application, a Language has many Phrases. I'm using accepts_nested_attributes_for, so by updating the parent I also save changes to associated phrases. Here my models:
class Language < ActiveRecord::Base has_many :phrases accepts_nested_attributes_for :phrases end
class Phrase < ActiveRecord::Base validates_presence_of :value belongs_to :language def before_validation print "\nValidating: #{self.value}\n" end end
I was expecting Rails to only validate the phrase that is being updated, here you can see it's validating all of the existing phrases:
$ script/console Loading development environment (Rails 2.3.5)
lang = Language.first
=> #<Language id: 1, name: "Italiano">
lang.phrases
=> [#<Phrase id: 7, value: "Buona notte", language_id: 1>, #<Phrase id: 10, value: "Ciao", language_id: 1>, #<Phrase id: 11, value: "Prego", language_id: 1>]
lang.phrases_attributes = [{:id => "7", :value => "Buon giorno"}]
=> [{:value=>"Buon giorno", :id=>"7"}]
lang.save
Validating: Buon giorno
Validating: Ciao
Validating: Prego
=> true
Validating all phrases is a real problem in my app, as I have tens of thousands; Is there a way to avoid this? Is this normal behavior for Rails?