小编luc*_*fer的帖子

我正在使用Active Admin gem为我的基于Quiz的小应用程序.但是当我执行rake db:migrate时,它给了我错误.以下是该命令的跟踪:

$ rake db:migrate RAILS_ENV=production --trace
** Invoke db:migrate (first_time)
** Invoke environment (first_time)
** Execute environment
** Invoke db:load_config (first_time)
** Invoke rails_env (first_time)
** Execute rails_env
** Execute db:load_config
** Execute db:migrate
==  DeviseCreateAdminUsers: migrating =========================================
-- create_table(:admin_users)
rake aborted!
An error has occurred, all later migrations canceled:

undefined method `database_authenticatable' for #<ActiveRecord::ConnectionAdapters::TableDefinition:0x9dee690>
/home/users/Documents/Quiz/db/migrate/20120509055635_devise_create_admin_users.rb:4:in `block in change'
/home/users/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.3/lib/active_record/connection_adapters/abstract/schema_statements.rb:160:in `create_table'
/home/users/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.3/lib/active_record/connection_adapters  /abstract_mysql_adapter.rb:432:in `create_table'
/home/users/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.3/lib/active_record/migration.rb:466:in `block in method_missing'
/home/users/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.3/lib/active_record/migration.rb:438:in `block in say_with_time'
/home/users/.rvm/rubies/ruby-1.9.2-p318/lib/ruby/1.9.1/benchmark.rb:295:in `measure'
/home/users/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.3/lib/active_record/migration.rb:438:in …