尝试can't convert nil to String我的postgresql数据库时出现rake db:create:all错误。
当我运行rake db:create:all时，我得到了
“你已经激活了rake 0.9.2.2，但是你的Gemfile需要rake 0.9.2。使用bundle exec可以解决这个问题。”
当我运行bundle exec rake db:create:all --trace时，我得到了
/Users/verdi/.rvm/gems/ruby-1.9.3-p194@global/gems/bundler-1.1.3/lib/bundler/runtime.rb:211: warning: Insecure world writable dir /usr/local in PATH, mode 040777
/Users/verdi/.rvm/gems/ruby-1.9.3-p194@global/gems/bundler-1.1.3/lib/bundler/runtime.rb:211: warning: Insecure world writable dir /usr/local in PATH, mode 040777
(in /Users/verdi/Documents/Rails/Terminal)
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/net-ping-1.5.0/lib/net/ping/external.rb:4: Use RbConfig instead of obsolete and deprecated Config.
rake aborted!
can't convert nil into String
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/cucumber-rails-0.5.2/lib/cucumber/rails3.rb:3:in `dirname'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/cucumber-rails-0.5.2/lib/cucumber/rails3.rb:3:in `<top (required)>'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/activesupport-3.0.9/lib/active_support/dependencies.rb:239:in `require'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/activesupport-3.0.9/lib/active_support/dependencies.rb:239:in `block in require'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/activesupport-3.0.9/lib/active_support/dependencies.rb:225:in `block in load_dependency'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/activesupport-3.0.9/lib/active_support/dependencies.rb:596:in `new_constants_in'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/activesupport-3.0.9/lib/active_support/dependencies.rb:225:in `load_dependency'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/activesupport-3.0.9/lib/active_support/dependencies.rb:239:in `require'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/cucumber-rails-0.5.2/lib/cucumber/rails.rb:2:in `<top (required)>'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194@global/gems/bundler-1.1.3/lib/bundler/runtime.rb:74:in `require'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194@global/gems/bundler-1.1.3/lib/bundler/runtime.rb:74:in `rescue in block in require'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194@global/gems/bundler-1.1.3/lib/bundler/runtime.rb:62:in `block in require'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194@global/gems/bundler-1.1.3/lib/bundler/runtime.rb:55:in `each'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194@global/gems/bundler-1.1.3/lib/bundler/runtime.rb:55:in `require'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194@global/gems/bundler-1.1.3/lib/bundler.rb:119:in `require'
/Users/verdi/Documents/Rails/Terminal/config/application.rb:7:in `<top (required)>'
/Users/verdi/Documents/Rails/Terminal/Rakefile:4:in `require'
/Users/verdi/Documents/Rails/Terminal/Rakefile:4:in `<top (required)>'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/rake-0.9.2/lib/rake/rake_module.rb:25:in `load'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/rake-0.9.2/lib/rake/rake_module.rb:25:in `load_rakefile'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/rake-0.9.2/lib/rake/application.rb:495:in `raw_load_rakefile'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/rake-0.9.2/lib/rake/application.rb:78:in `block in load_rakefile'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/rake-0.9.2/lib/rake/application.rb:129:in `standard_exception_handling'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/rake-0.9.2/lib/rake/application.rb:77:in `load_rakefile'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/rake-0.9.2/lib/rake/application.rb:61:in `block in run'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/rake-0.9.2/lib/rake/application.rb:129:in `standard_exception_handling'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/rake-0.9.2/lib/rake/application.rb:59:in `run'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/gems/rake-0.9.2/bin/rake:32:in `<top (required)>'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/bin/rake:23:in `load'
/Users/verdi/.rvm/gems/ruby-1.9.3-p194/bin/rake:23:in `<main>'
我正在关注Ryan Bates关于我克隆的现有App的教程： http://railscasts.com/episodes/342-migrating-to-postgresql?view=asciicast
答案 0 :(得分：1)
仔细检查您的database.yaml文件以确保所有值都在那里