Rails 4 simple_form has_many via checkboxes not preserving

Question

I am trying to embed an employee deduction table through checkboxes using simple_form. My code works, but the selected duplicate outputs are not saved in my table. I can’t understand why.

Here are my models.

class Employee < ActiveRecord::Base belongs_to :club has_many :employee_recurrents has_many :recurrents, :through => :employee_recurrents end class Recurrent < ActiveRecord::Base belongs_to :club has_many :employee_recurrents has_many :employees, :through => :employee_recurrents end class EmployeeRecurrent < ActiveRecord::Base belongs_to :employee belongs_to :recurrent end 

migration

 class CreateEmployeeRecurrents < ActiveRecord::Migration def change create_table :employee_recurrents, :id => false do |t| t.references :employee t.references :recurrent end add_index :employee_recurrents, [:employee_id, :recurrent_id] add_index :employee_recurrents, [:recurrent_id, :employee_id] end end 

The form

 <%= simple_form_for @employee, html: {class: 'form-horizontal' } do |f| %> <%= f.error_notification %> <%= f.input :first_name %> <%= f.input :last_name %> <%= f.association :recurrents, as: :check_boxes, label_method: :description, value_method: :id, label: 'Recurrent Deductions' %> <%= f.button :submit, class: 'btn btn-primary' %> <% end %> 

controller

 def employee_params params.require(:employee).permit(:first_name, :recurrent_ids) end 

here is my edited journal

 Started PATCH "/employees/1" for 127.0.0.1 at 2013-08-12 19:38:42 +0800 Processing by EmployeesController#update as HTML Parameters: {"utf8"=>"✓", "authenticity_token"=>"IwWzcT2qQJqHkTumWjb3OD5nJe9xLaA+YezMumer9X8=", "employee"=>{"job_id"=>"5", "manager_id"=>"", "first_name"=>"Mark", "recurrent_ids"=>["1", ""]}, "commit"=>"Update Employee", "id"=>"1"} [1m[36mActiveRecord::SessionStore::Session Load (1.2ms)[0m [1mSELECT "sessions".* FROM "sessions" WHERE "sessions"."session_id" = '9a8b066a4033f8fa2ed867371ffaa2a3' ORDER BY "sessions"."id" ASC LIMIT 1[0m [1m[35mUser Load (0.5ms)[0m SELECT "users".* FROM "users" WHERE "users"."id" = 1 LIMIT 1 [1m[36mEmployee Load (0.8ms)[0m [1mSELECT "employees".* FROM "employees" WHERE "employees"."id" = $1 ORDER BY last_name, first_name LIMIT 1[0m [["id", "1"]] Unpermitted parameters: recurrent_ids [1m[35m (0.6ms)[0m BEGIN [1m[36mEmployee Exists (1.1ms)[0m [1mSELECT 1 AS one FROM "employees" WHERE ("employees"."email" = ' [e-mail] ' AND "employees"."id" != 1 AND "employees"."club_id" = 1) LIMIT 1[0m [1m[35m (0.4ms)[0m COMMIT Redirected to http://localhost:3000/employees Completed 302 Found in 22ms (ActiveRecord: 4.6ms) 

Answer 1

I need the following strong parameters

 def employee_params params.require(:employee).permit(:first_name, :recurrent_ids => []) end