Keep Receiving an "Unknown attribute=user_id" error

Question

First time poster, long time lurker here. I have a Users model and controller for a little video game application for Rails that I'm currently making. So I've read a couple of answers on here regarding this issue, but none of the answers really seem to have helped me. People have suggested adding a "user_id" column to my Users table, but my point of contention is, I thought the "user_id" was automatically made in Rails? Even if I use a user.inspect, I still see a user_id=7show up on the page. However, I still get the unknown attribute error when attempting to create a game and assign to the current user. Any help would be most appreciated in pinpointing the cause and solution to this. Thanks!

app/controllers/users_controller.rb:

  class UsersController < ApplicationController
  skip_before_filter :require_authentication, only: [:new, :create]

  def index
    @users = User.all
  end

  def show
  end

  def new
    @user = User.new
  end

  def edit
    @user = current_user
  end

  def create
    @user = User.create!(user_params)
    session[:user_id] = @user.id
    redirect_to users_path, notice: "Hi #{@user.username}! Welcome to DuckGoose!"
  end

  def update
    current_user.update_attributes!(user_params)
    redirect_to users_path, notice: "Successfully updated profile."
  end

  def destroy
    @user = User.find(params[:id])
    @user.destroy
    redirect_to users_url, notice: 'User was successfully destroyed.'
  end

  private
    def user_params
      params.require(:user).permit(:username, :firstname, :lastname, :email, :password, :password_confirmation)
    end
end

app/config/routes.rb:

    NkuProject::Application.routes.draw do
      resources :users do
      resources :games
     end
     resources :sessions
     resources :games

     get "sign_out", to: "sessions#destroy"
     get "profile", to: "users#edit"

     root to: "sessions#new"
    end

app/controllers/games_controller.rb

class GamesController < ApplicationController
  def new
    @game = Game.new
  end

  def index
    @games = Game.all
  end

  def destroy
    @game = Game.find(params[:id])
    @game.destroy
    redirect_to games_url, notice: 'Game was successfully deleted.'
  end

  def create
    @game = current_user.games.build(game_params)
    if @game.save
      redirect_to @game, notice: "Game successfully added"
    else
      render :new
    end
  end

  def show
    @game = Game.find(params[:id])
  end

  private
  def game_params
    params.require(:game).permit!
  end
end

app/controllers/application_controller.rb

class ApplicationController < ActionController::Base
  # Prevent CSRF attacks by raising an exception.
  # For APIs, you may want to use :null_session instead.
  protect_from_forgery with: :exception
  before_filter :require_authentication

  def current_user
    @current_user ||= User.find_by(id: session[:user_id]) if session[:user_id].present?
  end
  helper_method :current_user


  def require_authentication
    if current_user
      true
    else
      redirect_to new_session_path
    end
  end
end

I'm sure I'm missing some code to put in for reference, but if I need anything else please let me know.

Answer 1

Looking at the way your controller actions are defined, I can safely say that User and Game have a 1-M relationship, i.e.,

class User < ActiveRecord::Base
  has_many :games
end

class Game < ActiveRecord::Base
  belongs_to :user
end

Now, based on that games table must have a field named user_id. Rails is not going to create it for you unless you specify it. You need to add field user_id in games table by creating a migration for the same. Right now, it doesn't seem like you have user_id foreign_key field in games table. Hence, the error while saving games record.