迁移不运行

Question

嘿，伙计们，我想把twitter-oauth功能添加到我的工作中。我安装了“无所不在的推特”创业板。当我试图运行我的迁移时，这是错误消息

C:\Sites\omniauth-tutorial>rake db:migrate
== 20160904075837 CreateUsers: migrating      ======================================
-- create_table(:users)
-- add_index(:users, :provider)
rake aborted!
StandardError: An error has occurred, this and all later migrations canceled:

SQLite3::SQLException: no such table: main.users: CREATE  INDEX "index_users_on_
provider" ON "users" ("provider")
C:/Sites/omniauth-tutorial/db/migrate/20160904075837_create_users.rb:10:in `block in change'
C:/Sites/omniauth-tutorial/db/migrate/20160904075837_create_users.rb:3:in `change'
C:in `migrate' ActiveRecord::StatementInvalid: SQLite3::SQLException: no such table: 
main.users: CREATE  INDEX "index_users_on_provider" ON "users"("provider")
C:/Sites/omniauth-tutorial/db/migrate/20160904075837_create_users.rb:10:in `block in change'
C:/Sites/omniauth-tutorial/db/migrate/20160904075837_create_users.rb:3:in `change'
C:in `migrate'
SQLite3::SQLException: no such table: main.users
C:/Sites/omniauth-tutorial/db/migrate/20160904075837_create_users.rb:10:in `block in change'
C:/Sites/omniauth-tutorial/db/migrate/20160904075837_create_users.rb:3:in `change'
C:in `migrate'
Tasks: TOP => db:migrate
(See full trace by running task with --trace)

这是我的迁移文件

class CreateUsers < ActiveRecord::Migration
  def change
    create_table :users do |t|
      t.string :provider, null: false
      t.string :uid, null: false
      t.string :name
      t.string :location
      t.string :image_url
      t.string :url
      add_index :users, :provider
      add_index :users, :uid
      add_index :users, [:provider, :uid], unique: true

      t.timestamps null: false
    end
  end
end

请知道如何解决这一问题吗？

Answer 1

您需要将add_index命令放在create_table之后

class CreateUsers < ActiveRecord::Migration
  def change
    create_table :users do |t|
      t.string :provider, null: false
      t.string :uid, null: false
      t.string :name
      t.string :location
      t.string :image_url
      t.string :url

      t.timestamps null: false
    end

    add_index :users, :provider
    add_index :users, :uid
    add_index :users, [:provider, :uid], unique: true
  end
end