ruby on rails - rake db:migrate is not working

Question

I'm working through the rails tutorial and have gotten stuck. Starting at Listing 8.16 I have made the following modifications to <timestamp>_add_remember_token_to_users.rb:

class AddRememberTokenToUsers < ActiveRecord::Migration
  def change
    add_column :users, :remember_token, :string
    add_index  :users, :remember_token
  end
end

The guide then says to update dev & test db as usual:

$ bundle exec rake db:migrate
$ bundle exec rake db:test:prepare

My User test for the *remember_token* is still failing so I took a look at the user table in dev and tests database with command line sqlite3. They look like this:

sqlite> .schema users
CREATE TABLE "users" (
   "id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, 
   "name" varchar(255), 
   "email" varchar(255), 
   "created_at" datetime NOT NULL, 
   "updated_at" datetime NOT NULL, 
   "password_digest" varchar(255));
CREATE UNIQUE INDEX "index_users_on_email" ON "users" ("email");

It seems like my migration has not been run yet but I do not know how to force it to run.

Answer 1

Try to rebuild your database structure(WARNING: all db-data will be lost):

rake db:drop:all
rake db:create:all
rake db:migrate

If you use Rails < 4.1, don't forget to prepare test database:

rake db:test:prepare

This is the easiest solution since you are working with tutorial. However in production or having important data in development you should take time to investigate the issue. In this case you most likely had created an empty migration, ran rake db:migrate, then added instructions to the migration, so you don't see a new field and further rake db:migrate does nothing. To resolve this issue you need to comment your change instructions, perform rake db:rollback, uncomment instructions and then rake db:migrate to apply instructions you missed.