habtm relation, cannot populate join table

rubyonrails-talk
1

Hai friends, I hav two models related with habtm

class User < ActiveRecord::Base   has_and_belongs_to_many :station,                           :join_table => "stations_users",                           :foreign_key => "user_id",                           :association_foreign_key => "station_id"

class Station < ActiveRecord::Base   has_and_belongs_to_many :user end

When i create a new user its user_id and the station _id is not inserted into the "stations_users" table.I hav used scaffolding 4 creating these two models.How can i insert the fields for the join table also when a user is created? Can any one help me?

Thanks and regards, Veena

2

Hai friends, I hav two models related with habtm

class User < ActiveRecord::Base has_and_belongs_to_many :station, :join_table => "stations_users", :foreign_key => "user_id", :association_foreign_key => "station_id"

Shouldn't this be    has_and_belongs_to_many :stations

The plurality is important. Also with that change the join_table, foreign_key and association_foreign key options are unnecessary since those are the defaults.

class Station < ActiveRecord::Base has_and_belongs_to_many :user

And this should be     has_and_belongs_to_many :users

end

When i create a new user its user_id and the station _id is not inserted into the "stations_users" table.I hav used scaffolding 4 creating these two models.How can i insert the fields for the join table also when a user is created? Can any one help me?

Not sure that this is your problem, but I wouldn't be surprised.

3

Hai Rick,

   I have made the change you hav told. Still the join table is not been populated. These are my migration data.Is there any problem with this? ..................................................... class CreateNewStations < ActiveRecord::Migration   def self.up     create_table :stations do |t|       t.string :name       t.integer :district_id       t.string :MDT_id       t.string :sim_no       t.decimal :longitude, :precision=>10, :scale=>6       t.decimal :latitude, :precision=>10, :scale=>6       t.integer :user_id       t.timestamps

    end     create_table :stations_users, :id => false do |t|       t.integer :user_id       t.integer :station_id     end   end

  def self.down    drop_table :stations_users rescue nil     drop_table :stations   end end ...........................................................

class CreateUsers < ActiveRecord::Migration   def self.up     create_table :users do |t|       t.string :name       t.string :username       t.string :hashed_password       t.string :salt       t.string :status       t.string :phone       t.string :email       t.integer :station_id       t.timestamps     end   end

  def self.down     drop_table :users   end end

Thanks and Regards, Veena

4

Hai Rick,

I have made the change you hav told. Still the join table is not been populated. These are my migration data.Is there any problem with this? ..................................................... class CreateNewStations < ActiveRecord::Migration def self.up create_table :stations do |t| t.string :name t.integer :district_id t.string :MDT_id t.string :sim_no t.decimal :longitude, :precision=>10, :scale=>6 t.decimal :latitude, :precision=>10, :scale=>6 t.integer :user_id

I don't think you want this field. This would be there if you had

    class Stations < ActiverRecord::Base         belongs_to :user     end

but you indicated that each station could have many users, and each user could have many stations, thus the habtm relations.