l'ajout d'une clé étrangère dans la table
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26-10-2019 - |
Question
Je continue à obtenir cette exception: "SQLite3::SQLException: no such column: books.user_id: SELECT "books".* FROM "books" WHERE ("books".user_id = 4)"
. Ce qui sonne comme il n'y a pas user_id dans la table des livres.
Je viens d'installer le plugin Foreigner et ajouté "t.integer :user_id, :null => false"
et "add_foreign_key(:books, :users)"
dans le fichier de migration du livre. Je courus "rake db:migrate"
, mais il me donne la même exception.
J'utilise Rails 3 sous Windows et l'utilisateur Legs aux Authentifier.
HOME VIEW
<p><%= link_to "Add new Book",:controller =>"book", :action => 'new' %></p>
<% @books.each do |b| %>
<p><%= b.author%></p>
<p><%= b.title%></p>
<%end%>
HOME CONTRÔLEUR
class HomeController < ApplicationController
def index
@user = current_user
@user.books||=Book.new
@books=@user.books
end
end
LIVRE CONTRÔLEUR
class BookController < ApplicationController
def new
@books = Book.new
# redirect_to :controller=>"home" ,:action=>"index"
end
def create
@books = Book.new(params[:book])
if @books.save
render "home/index"
#redirect_to :controller=>"home" ,:action=>"index"
else
render :action => 'new'
end
end
CREATE TABLE / MIGRATION LIVRE
class CreateBooks < ActiveRecord::Migration
def self.up
create_table :books do |t|
t.text :title
t.text :author
t.integer :user_id, :null => false
t.timestamps
end
add_foreign_key(:books, :users)
end
LIVRE VIEW
<h1>Book#new</h1>
<%= form_for(:book) do |f| %>
<p><%= f.text_field :title %></p>
<p><%= f.text_field :author %></p>
<p><%= f.submit "Add book"%>
LIVRE MODÈLE
class Book < ActiveRecord::Base
belongs_to :user
end
MODÈLE UTILISATEUR
class User < ActiveRecord::Base
has_many :books
# Include default devise modules. Others available are:
# :token_authenticatable, :lockable, :timeoutable and :activatable
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable
# Setup accessible (or protected) attributes for your model
attr_accessible :email, :password, :password_confirmation,:firstname,:lastname,:school,:major,:sex,:zipcode
end
ROUTE Campus :: Application.routes.draw faire obtenir "livre / index"
get "book/edit"
get "book/new"
get "home/edit"
devise_for :users
resources :book
root :to=> "home#index"
match '/book/new' =>"home#index"
end
BASE DE DONNÉES SCHEMA
ActiveRecord::Schema.define(:version => 20110609055608) do
create_table "books", :force => true do |t|
t.text "title"
t.text "author"
t.integer "user_id", :null => false
t.datetime "created_at"
t.datetime "updated_at"
end
create_table "courses", :force => true do |t|
t.string "name"
t.datetime "created_at"
t.datetime "updated_at"
end
create_table "strong_ins", :force => true do |t|
t.string "subject"
t.string "topic"
t.text "description"
t.datetime "created_at"
t.datetime "updated_at"
end
create_table "users", :force => true do |t|
t.string "email", :default => "", :null => false
t.string "encrypted_password", :limit => 128, :default => "", :null => false
t.string "password_salt", :default => "", :null => false
t.string "reset_password_token"
t.string "remember_token"
t.datetime "remember_created_at"
t.integer "sign_in_count", :default => 0
t.datetime "current_sign_in_at"
t.datetime "last_sign_in_at"
t.string "current_sign_in_ip"
t.string "last_sign_in_ip"
t.datetime "created_at"
t.datetime "updated_at"
t.string "firstname"
t.string "lastname"
t.text "school"
t.text "major"
t.string "sex"
t.integer "zipcode"
end
add_index "users", ["email"], :name => "index_users_on_email", :unique => true
add_index "users", ["reset_password_token"], :name => "index_users_on_reset_password_token", :unique => true
create_table "weak_ins", :force => true do |t|
t.string "subject"
t.string "topic"
t.text "description"
t.datetime "created_at"
t.datetime "updated_at"
end
end
La solution
La colonne user_id
doit apparaître dans le schéma après l'exécution de la migration. Ce n'est pas dans votre liste, donc je dirais que c'est le problème. Assurez-vous que rake db:migrate
termine sans erreurs. Vous pouvez refaire la migration avec rake db:rollback && rake db:migrate
, si nécessaire.