导轨4耙中止！ on heroku

Question

rake db：migrate在开发中运行良好，应用程序也一样。只有Heroku的是我遇到的麻烦

$ heroku run rake db:migrate 

Running `rake db:migrate` attached to terminal... up, run.5905 
-- create_table(:users) 
-- create_table(:users) 
rake aborted! 
ActiveRecord::MigrationProxy#disable_ddl_transaction delegated to 
migration.disable_ddl_transaction, but migration is nil: 
#<struct ActiveRecord::MigrationProxy name="DeviseCreateAdmins", 
version=20130802210826, filename="/app/db/migrate/20130802210826_devise_create_admins.rb", 
scope="" 

迁移文件：

class DeviseCreateAdmins < ActiveRecord::Migration 
    create_table :users do |t| 
    t.database_authenticatable 
    t.confirmable 
    t.recoverable 
    t.rememberable 
    t.trackable 
    t.timestamps 
    end 
end 

有没有人有关于为什么迁移是失败的任何想法？

Answer 1

你缺少方法名，

class DeviseCreateAdmins < ActiveRecord::Migration 
    def change 
    create_table :users do |t| 
     t.database_authenticatable 
     t.confirmable 
     t.recoverable 
     t.rememberable 
     t.trackable 
     t.timestamps 
    end 
    end 
end 

通知def change开头。