rake db:migrate 不做任何事情

Question

我正在学习 onemonthrails 教程，并且正在学习“新用户注册和登录”课程。我正确地遵循了所有步骤，但我遇到了一个错误：

"ActiveRecord::StatementInvalid in Devise::RegistrationsController#new

找不到表“用户””

我的终端与老师的终端唯一不同的是“运行 db:migrate”，它什么都不做……

完整的错误跟踪给了我这个：

activerecord (4.1.0) lib/active_record/connection_adapters/sqlite3_adapter.rb:512:in `table_structure'
activerecord (4.1.0) lib/active_record/connection_adapters/sqlite3_adapter.rb:387:in `columns'
activerecord (4.1.0) lib/active_record/connection_adapters/schema_cache.rb:93:in `block in prepare_default_proc'
activerecord (4.1.0) lib/active_record/connection_adapters/schema_cache.rb:44:in `yield'
activerecord (4.1.0) lib/active_record/connection_adapters/schema_cache.rb:44:in `columns'
activerecord (4.1.0) lib/active_record/model_schema.rb:214:in `columns'
activerecord (4.1.0) lib/active_record/model_schema.rb:223:in `columns_hash'
activerecord (4.1.0) lib/active_record/inheritance.rb:180:in `subclass_from_attributes?'
activerecord (4.1.0) lib/active_record/inheritance.rb:23:in `new'
devise (3.1.2) lib/devise/models/registerable.rb:20:in `new_with_session'
devise (3.1.2) app/controllers/devise/registrations_controller.rb:92:in `build_resource'
devise (3.1.2) app/controllers/devise/registrations_controller.rb:7:in `new'
actionpack (4.1.0) lib/action_controller/metal/implicit_render.rb:4:in `send_action'
actionpack (4.1.0) lib/abstract_controller/base.rb:189:in `process_action'
actionpack (4.1.0) lib/action_controller/metal/rendering.rb:10:in `process_action'
actionpack (4.1.0) lib/abstract_controller/callbacks.rb:20:in `block in process_action'
activesupport (4.1.0) lib/active_support/callbacks.rb:113:in `call'
activesupport (4.1.0) lib/active_support/callbacks.rb:113:in `call'
activesupport (4.1.0) lib/active_support/callbacks.rb:229:in `block in halting'
activesupport (4.1.0) lib/active_support/callbacks.rb:229:in `call'
activesupport (4.1.0) lib/active_support/callbacks.rb:229:in `block in halting'
activesupport (4.1.0) lib/active_support/callbacks.rb:166:in `call'
activesupport (4.1.0) lib/active_support/callbacks.rb:166:in `block in halting'
activesupport (4.1.0) lib/active_support/callbacks.rb:166:in `call'
activesupport (4.1.0) lib/active_support/callbacks.rb:166:in `block in halting'
activesupport (4.1.0) lib/active_support/callbacks.rb:166:in `call'
activesupport (4.1.0) lib/active_support/callbacks.rb:166:in `block in halting'
activesupport (4.1.0) lib/active_support/callbacks.rb:166:in `call'
activesupport (4.1.0) lib/active_support/callbacks.rb:166:in `block in halting'
activesupport (4.1.0) lib/active_support/callbacks.rb:149:in `call'
activesupport (4.1.0) lib/active_support/callbacks.rb:149:in `block in halting_and_conditional'
activesupport (4.1.0) lib/active_support/callbacks.rb:149:in `call'
activesupport (4.1.0) lib/active_support/callbacks.rb:149:in `block in halting_and_conditional'
activesupport (4.1.0) lib/active_support/callbacks.rb:86:in `call'
activesupport (4.1.0) lib/active_support/callbacks.rb:86:in `run_callbacks'
actionpack (4.1.0) lib/abstract_controller/callbacks.rb:19:in `process_action'
actionpack (4.1.0) lib/action_controller/metal/rescue.rb:29:in `process_action'
actionpack (4.1.0) lib/action_controller/metal/instrumentation.rb:31:in `block in process_action'
activesupport (4.1.0) lib/active_support/notifications.rb:159:in `block in instrument'
activesupport (4.1.0) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (4.1.0) lib/active_support/notifications.rb:159:in `instrument'
actionpack (4.1.0) lib/action_controller/metal/instrumentation.rb:30:in `process_action'
actionpack (4.1.0) lib/action_controller/metal/params_wrapper.rb:250:in `process_action'
activerecord (4.1.0) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
actionpack (4.1.0) lib/abstract_controller/base.rb:136:in `process'
actionview (4.1.0) lib/action_view/rendering.rb:30:in `process'
actionpack (4.1.0) lib/action_controller/metal.rb:195:in `dispatch'
actionpack (4.1.0) lib/action_controller/metal/rack_delegation.rb:13:in `dispatch'
actionpack (4.1.0) lib/action_controller/metal.rb:231:in `block in action'
actionpack (4.1.0) lib/action_dispatch/routing/route_set.rb:80:in `call'
actionpack (4.1.0) lib/action_dispatch/routing/route_set.rb:80:in `dispatch'
actionpack (4.1.0) lib/action_dispatch/routing/route_set.rb:48:in `call'
actionpack (4.1.0) lib/action_dispatch/routing/mapper.rb:45:in `call'
actionpack (4.1.0) lib/action_dispatch/journey/router.rb:71:in `block in call'
actionpack (4.1.0) lib/action_dispatch/journey/router.rb:59:in `each'
actionpack (4.1.0) lib/action_dispatch/journey/router.rb:59:in `call'
actionpack (4.1.0) lib/action_dispatch/routing/route_set.rb:676:in `call'
warden (1.2.3) lib/warden/manager.rb:35:in `block in call'
warden (1.2.3) lib/warden/manager.rb:34:in `catch'
warden (1.2.3) lib/warden/manager.rb:34:in `call'
rack (1.5.2) lib/rack/etag.rb:23:in `call'
rack (1.5.2) lib/rack/conditionalget.rb:25:in `call'
rack (1.5.2) lib/rack/head.rb:11:in `call'
actionpack (4.1.0) lib/action_dispatch/middleware/params_parser.rb:27:in `call'
actionpack (4.1.0) lib/action_dispatch/middleware/flash.rb:254:in `call'
rack (1.5.2) lib/rack/session/abstract/id.rb:225:in `context'
rack (1.5.2) lib/rack/session/abstract/id.rb:220:in `call'
actionpack (4.1.0) lib/action_dispatch/middleware/cookies.rb:560:in `call'
activerecord (4.1.0) lib/active_record/query_cache.rb:36:in `call'
activerecord (4.1.0) lib/active_record/connection_adapters/abstract/connection_pool.rb:621:in `call'
activerecord (4.1.0) lib/active_record/migration.rb:380:in `call'
actionpack (4.1.0) lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'
activesupport (4.1.0) lib/active_support/callbacks.rb:82:in `run_callbacks'
actionpack (4.1.0) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
actionpack (4.1.0) lib/action_dispatch/middleware/reloader.rb:73:in `call'
actionpack (4.1.0) lib/action_dispatch/middleware/remote_ip.rb:76:in `call'
actionpack (4.1.0) lib/action_dispatch/middleware/debug_exceptions.rb:17:in `call'
actionpack (4.1.0) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
railties (4.1.0) lib/rails/rack/logger.rb:38:in `call_app'
railties (4.1.0) lib/rails/rack/logger.rb:20:in `block in call'
activesupport (4.1.0) lib/active_support/tagged_logging.rb:68:in `block in tagged'
activesupport (4.1.0) lib/active_support/tagged_logging.rb:26:in `tagged'
activesupport (4.1.0) lib/active_support/tagged_logging.rb:68:in `tagged'
railties (4.1.0) lib/rails/rack/logger.rb:20:in `call'
actionpack (4.1.0) lib/action_dispatch/middleware/request_id.rb:21:in `call'
rack (1.5.2) lib/rack/methodoverride.rb:21:in `call'
rack (1.5.2) lib/rack/runtime.rb:17:in `call'
activesupport (4.1.0) lib/active_support/cache/strategy/local_cache_middleware.rb:26:in `call'
rack (1.5.2) lib/rack/lock.rb:17:in `call'
actionpack (4.1.0) lib/action_dispatch/middleware/static.rb:64:in `call'
rack (1.5.2) lib/rack/sendfile.rb:112:in `call'
railties (4.1.0) lib/rails/engine.rb:514:in `call'
railties (4.1.0) lib/rails/application.rb:144:in `call'
rack (1.5.2) lib/rack/lock.rb:17:in `call'
rack (1.5.2) lib/rack/content_length.rb:14:in `call'
rack (1.5.2) lib/rack/handler/webrick.rb:60:in `service'
/Users/pablofaust/.rvm/rubies/ruby-2.1.1/lib/ruby/2.1.0/webrick/httpserver.rb:138:in `service'
/Users/pablofaust/.rvm/rubies/ruby-2.1.1/lib/ruby/2.1.0/webrick/httpserver.rb:94:in `run'
/Users/pablofaust/.rvm/rubies/ruby-2.1.1/lib/ruby/2.1.0/webrick/server.rb:295:in `block in start_thread'

我该怎么办？

Answer 1

显然，您的 migrate 正在尝试对 Users 表执行某些操作，但它不存在。尝试rake db:migrate VERSION=0，然后再次尝试rake db:migrate，重新开始*。如果您在 down-rake 上遇到错误，您可以进入您的数据库并删除数据库并重新创建它以重新开始*。

如果您仍然遇到问题，那么您的迁移文件中一定有错字。

*请注意，“重新开始”将删除数据库中的所有数据（如果有的话）。

Answer 2

将数据库迁移为：​​--

rake db:migrate

Answer 3

首先确保数据库存在

rake db:create

然后运行 ​​devise 创建的迁移

rake db:migrate