1.Could not find gem 'sqlite3 (>= 0)' in any of the gem sources listed in you
r Gemfile
解决：sudo gem install sqlite3-ruby
2.ERROR: While executing gem ... (Gem::FilePermissionError)
You don't have write permissions into the /usr/local/lib/ruby/gems/1.9.1 director.y
解决：权限问题，前面加个sudo
3.rails 3遇到 Could not find a JavaScript runtime execjs错误（ubuntu）
解决：
sudo apt-get install python-software-properties
sudo add-apt-repository ppa:chris-lea/node.js
sudo apt-get update
sudo apt-get install nodejs