Rails 4 SQLite3 :: SQLException错误

Question

I have a devise User model which I want to add a admin boolean field so I ran

rails generate migration add_admin_to_users admin:boolean which created the following migration

class AddAdminToUsers < ActiveRecord::Migration
 def change
  add_column :users, :admin, :boolean
 end
end

However when I run rake db:migrate I keep getting the following error

SQLite3::SQLException: no such table: users: ALTER TABLE "users" ADD "admin" boolean/home/notebook/.rvm/gems/ruby-2.0.0-p353/gems/sqlite3-1.3.8/lib/sqlite3/database.rb:91:in `initialize'

I have tried to rake db:migrate VERSION=0 to rollback to the beginning and redone rake db:migrate again but I keep getting the same error

Here is my user model migration file

class DeviseCreateUsers < ActiveRecord::Migration
  def change
   create_table(:users) do |t|
  ## Database authenticatable
  t.string :email,              :null => false, :default => ""
  t.string :encrypted_password, :null => false, :default => ""

  ## Recoverable
  t.string   :reset_password_token
  t.datetime :reset_password_sent_at

  ## Rememberable
  t.datetime :remember_created_at

  ## Trackable
  t.integer  :sign_in_count, :default => 0, :null => false
  t.datetime :current_sign_in_at
  t.datetime :last_sign_in_at
  t.string   :current_sign_in_ip
  t.string   :last_sign_in_ip

  ## Confirmable
  t.string   :confirmation_token
  t.datetime :confirmed_at
  t.datetime :confirmation_sent_at
  t.string   :unconfirmed_email # Only if using reconfirmable

  ## Lockable
  # t.integer  :failed_attempts, :default => 0, :null => false # Only if lock strategy is :failed_attempts
  # t.string   :unlock_token # Only if unlock strategy is :email or :both
  # t.datetime :locked_at
  t.timestamps
end

add_index :users, :email,                :unique => true
add_index :users, :reset_password_token, :unique => true
add_index :users, :confirmation_token,   :unique => true
# add_index :users, :unlock_token,         :unique => true
end
end

My db/schema.rb file is as follows:

ActiveRecord::Schema.define(version: 20140217093954) do
  create_table "entities", force: true do |t|
   t.string   "entity"
   t.string   "genre"
   t.string   "url"
   t.datetime "created_at"
   t.datetime "updated_at"
end

   add_index "entities", ["entity"], name: "index_entities_on_entity", unique: true

end

Answer 1

It sounds like your development database is not in sync with the schema (or what you think the schema is). Running database migrations is intended for incremental changes and not intended to be be a way to rollback the database and run from the first migration. For this you want to use rake db:reset , which will drop the database and load the schema from db/schema. This post has a good overview of the different database rake commands.

Answer 2

Your database has not users table, you need to create users table first:

rails g migration create_users

And put that migration before the one you are trying to run now, ie changing its timestamp.

An easier option is to add in your current file:

class AddAdminToUsers < ActiveRecord::Migration
 def change
  create_table :users
  add_column :users, :admin, :boolean
 end
end

Whatever of the solutions you apply, you have a problem with the order of your migrations, search inside migrate folder for a migration that actually creates users table.