windows下ruby on rails 数据迁移报错rake aborted! uninitialized constant Rake::DSL
window下配置完ruby1.9.2和rails3.09之后进行数据迁移报错：
C:\Users\jia\webapps>rake db:create(in C:/Users/jia/webapps)rake aborted!uninitialized constant Rake::DSLC:/Ruby192/lib/ruby/1.9.1/rake.rb:2482:in `const_missing'C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/tasklib.rb:8:in `<class:TaskLib>'C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/tasklib.rb:6:in `<module:Rake>'C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/tasklib.rb:3:in `<top (required)>'C:/Ruby192/lib/ruby/gems/1.9.1/gems/rdoc-3.8/lib/rdoc/task.rb:37:in `require'C:/Ruby192/lib/ruby/gems/1.9.1/gems/rdoc-3.8/lib/rdoc/task.rb:37:in `<top (required)>'C:/Ruby192/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/tasks/documentation.rake:2:in `require'C:/Ruby192/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/tasks/documentation.rake:2:in `<top (required)>'C:/Ruby192/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/tasks.rb:15:in `load'C:/Ruby192/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/tasks.rb:15:in `block in <top (required)>'C:/Ruby192/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/tasks.rb:6:in `each'C:/Ruby192/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/tasks.rb:6:in `<top (required)>'C:/Ruby192/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/application.rb:215:in `require'C:/Ruby192/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/application.rb:215:in `initialize_tasks'C:/Ruby192/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/application.rb:139:in `load_tasks'C:/Ruby192/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/application.rb:77:in `method_missing'C:/Users/jia/webapps/Rakefile:7:in `<top (required)>'C:/Ruby192/lib/ruby/1.9.1/rake.rb:2373:in `load'C:/Ruby192/lib/ruby/1.9.1/rake.rb:2373:in `raw_load_rakefile'C:/Ruby192/lib/ruby/1.9.1/rake.rb:2007:in `block in load_rakefile'C:/Ruby192/lib/ruby/1.9.1/rake.rb:2058:in `standard_exception_handling'C:/Ruby192/lib/ruby/1.9.1/rake.rb:2006:in `load_rakefile'C:/Ruby192/lib/ruby/1.9.1/rake.rb:1991:in `run'C:/Ruby192/bin/rake:31:in `<main>'
gem install rake
C:\Users\jia\webapps>gem install rakeSuccessfully installed rake-0.9.21 gem installedInstalling ri documentation for rake-0.9.2...Installing RDoc documentation for rake-0.9.2...
