Rails 3.1.rc1和accept_nested_attributes_for

class Survey < ActiveRecord::Base
  set_primary_key :survey_id # I\'m using external DB
  belongs_to :user #UPDATED
  has_many :questions, :dependent => :destroy
  accept_nested_attributes_for :questions
end

class Question < ActiveRecord::Base
  set_primary_key :question_id # I\'m using external DB
  belogns_to :survey
end

>> params = {\"title\"=>\"Survey 1\", \"questions_attributes\"=>{\"0\"=>{\"title\"=>\"Question 2\"}}}
>> survey = User.first.surveys.build(params) #UPDATED
>> survey.questions.size
=> 2
>> survey = User.first.surveys.new(params)
>> survey.questions.size
=> 1