每当我尝试在我的rails项目中使用rake时，它会向我抛出以下消息。我尝试重新安装ruby，rails，rake，重新创建项目，使用 sudo 启动我的 rake db：migrate 但似乎没有任何工作...... 我通过scaffold命令创建了对象：
rails generate scaffold User nom:string email:string
在此命令成功执行后，我启动
rake db:migrate
它会返回此消息：
rake aborted!
GONE
/var/lib/gems/1.9.1/gems/railties-3.0.5/lib/rails/tasks/documentation.rake:1:in `require'
/var/lib/gems/1.9.1/gems/railties-3.0.5/lib/rails/tasks/documentation.rake:1:in `<top (required)>'
/var/lib/gems/1.9.1/gems/railties-3.0.5/lib/rails/tasks.rb:15:in `load'
/var/lib/gems/1.9.1/gems/railties-3.0.5/lib/rails/tasks.rb:15:in `block in <top (required)>'
/var/lib/gems/1.9.1/gems/railties-3.0.5/lib/rails/tasks.rb:6:in `each'
/var/lib/gems/1.9.1/gems/railties-3.0.5/lib/rails/tasks.rb:6:in `<top (required)>'
/var/lib/gems/1.9.1/gems/railties-3.0.5/lib/rails/application.rb:213:in `require'
/var/lib/gems/1.9.1/gems/railties-3.0.5/lib/rails/application.rb:213:in `initialize_tasks'
/var/lib/gems/1.9.1/gems/railties-3.0.5/lib/rails/application.rb:139:in `load_tasks'
/var/lib/gems/1.9.1/gems/railties-3.0.5/lib/rails/application.rb:77:in `method_missing'
/home/bassochette/Dev/rails/tuto/demo_app/Rakefile:7:in `<top (required)>'
(See full trace by running task with --trace)
ps：我是初学者和学习阶段的新手。