ruby on rails - update_attributes not working for many-to-many nested attributes -

i have nested attributes in models such:

class employee < activerecord::base   has_one :user, :as => :user_role, :dependent => :destroy   accepts_nested_attributes_for :user, :allow_destroy => true end  class user < activerecord::base   has_one :person, :as => :person_role, :dependent => :destroy   belongs_to :user_role, :polymorphic => true   accepts_nested_attributes_for :person, :allow_destroy => true end  class person < activerecord::base   has_many :address_person_links, :dependent => :destroy   has_many :addresses, :through => :address_person_links, :uniq => true, :dependent => :destroy    belongs_to :person_role, :polymorphic => true    accepts_nested_attributes_for :addresses, :allow_destroy => true end  class addresspersonlink < activerecord::base   belongs_to :address   belongs_to :person end  class address < activerecord::base   has_many :address_person_links, :dependent => :destroy   has_many :people, :through => :address_person_links, :uniq => true end 

when call @employee.update_attributes(params[:employee]) controller updates except address. if raise params.inspect , copy variable in script/console, work. example:

>> e = employee.find(8) => #<employee id: 8, active: true, admin: false, created_at: "2010-10-06 20:05:01", updated_at: "2010-10-06 20:11:20"> >>address = a.user.person.addresses[0] => #<address id: 10, address1: "225 3rd ave", address2: "", address3: "", city: "sacramento", state_id: 5, zip_code: "95814", country_id: 1, contact_type_id: 2, created_at: "2010-10-06 20:05:01", updated_at: "2010-10-06 22:40:06"> >> params = {"commit"=>"update", ?>  "_method"=>"put", ?>  "authenticity_token"=>"sygfndbt4sb00wsjjxnpf4fnhrt4hbhcy7w+ienpc/k=", ?>  "id"=>"8", ?>  "employee"=>{"user_attributes"=>{"person_attributes"=>{"addresses_attributes"=>{"0"=>{"address1"=>"225 3rd ave suite 777", ?>  "city"=>"sacramento", ?>  "contact_type_id"=>"2", ?>  "address2"=>"", ?>  "address3"=>"", ?>  "zip_code"=>"95814", ?>  "country_id"=>"1", ?>  "id"=>"10", ?>  "state_id"=>"5"}}, ?>  "prefix"=>"", ?>  "email_addresses_attributes"=>{"0"=>{"contact_type_id"=>"2", ?>  "id"=>"16", ?>  "email"=>"first@example.com"}}, ?>  "id"=>"16", ?>  "last_name"=>"last", ?>  "suffix"=>"", ?>  "phone_numbers_attributes"=>{"0"=>{"number"=>"9165555555", ?>  "contact_type_id"=>"1", ?>  "extension"=>"", ?>  "id"=>"16"}}, ?>  "first_name"=>"first"}, ?>  "password_confirmation"=>"321321", ?>  "id"=>"16", ?>  "password"=>"321321", ?>  "login"=>"third"}, ?>  "admin"=>"0", ?>  "active"=>"1"}} => # outputs hash created >> e.update_attributes(params["employee"]) # no longer symbols string keys => true >> address => #<address id: 10, address1: "225 3rd ave suite 777", address2: "", address3: "", city: "sacramento", state_id: 5, zip_code: "95814", country_id: 1, contact_type_id: 2, created_at: "2010-10-06 20:05:01", updated_at: "2010-10-06 22:40:16"> 

so can see address was updated script/console not controller.

if information overload, simple version of question is:
why doesn't address updated?

i able @ problem today. quick fix stumbled upon because dealing issue: addresses weren't being deleted when deleted employees, users or people. fix this:

class addresspersonlink < activerecord::base   # how adding dependent => destroy fixed problem   # having updating well.   belongs_to :address, :dependent => :destroy   belongs_to :person end