ruby on rails - Nested Attributes Update with a different Primary Key -

i have 2 models, face error when updating them. have used nested attributes.

 class channel < activerecord::base     self.primary_key = 'id'      has_many :channel_mappings , primary_key: 'channel_name', foreign_key: 'channel_name'      attr_accessible :channel_name, :channel_mappings_attributes      validates_presence_of :channel_name      accepts_nested_attributes_for :channel_mappings, :allow_destroy => true end 

2nd model

class channelmapping < activerecord::base   self.primary_key = 'src_channel'    belongs_to :channel, primary_key: 'channel_name', foreign_key: 'channel_name'    attr_accessible :src_channel, :channel_name , :src_file_type  end 

update method

def update         @channel = channel.find(params[:id])          if @channel.update_attributes(params[:channel])             redirect_to @channel, notice: 'channel updated.'         else             render action: 'edit'         end     end 

error

  type: activerecord::recordnotfound       message:  couldn't find channelmapping id=any name channel id=2 

i know it' primary key overwritten. useful

db/schema.rb

create_table "channels", :force => true |t|     t.text    "channel_name",                                  :null => false     t.string  "internal_flag",                  :limit => nil     t.string  "exception_flag",                 :limit => nil   end  create_table "channel_mappings", :id => false, :force => true |t|     t.text    "src_channel",   :null => false     t.text    "channel_name",  :null => false   end 

you try - @channel.attributes = params[:channel] instead of @channel.update_attributes(params[:channel])

this set attributes without save.

then can call -

@channel.save

this save attributes.

the error seems record not found rather update revert like.

check error log first , if needed post here if nothing works.

it better use if else conditions as:

if @channel.save #record saved else #error in save end 

then can know it's going.