Ruby on rails rails服务器（4.0.0）无法启动-错误：LoadError:8 lib/mysql2.rb:8:in`require'；：libmysqlclient.so.18_Ruby On Rails_Ruby_Ruby On Rails 4

Ruby on rails rails服务器（4.0.0）无法启动-错误：LoadError:8 lib/mysql2.rb:8:in`require'；：libmysqlclient.so.18

ruby-on-rails ruby ruby-on-rails-4

Ruby on rails rails服务器（4.0.0）无法启动-错误：LoadError:8 lib/mysql2.rb:8:in`require'；：libmysqlclient.so.18,ruby-on-rails,ruby,ruby-on-rails-4,Ruby On Rails,Ruby,Ruby On Rails 4,我无法启动rails服务器。错误显示： $ rails server /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2a.rb:8:in `require': libmysqlclient.so.18: cannot open shared object file: No such file or directory - /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/li

我无法启动rails服务器。错误显示：

$ rails server
/usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2a.rb:8:in `require': libmysqlclient.so.18: cannot open shared object file: No such file or directory - /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so (LoadError)
    from /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2.rb:8:in `<top (required)>'
    from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.3.5/lib/bundler/runtime.rb:72:in `require'
    from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.3.5/lib/bundler/runtime.rb:72:in `block (2 levels) in require'
    from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.3.5/lib/bundler/runtime.rb:70:in `each'
    from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.3.5/lib/bundler/runtime.rb:70:in `block in require'
    from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.3.5/lib/bundler/runtime.rb:59:in `each'
    from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.3.5/lib/bundler/runtime.rb:59:in `require'
    from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.3.5/lib/bundler.rb:132:in `require'
    from /home/marslo/Study/Codes/Ruby/RailsBegin/config/application.rb:7:in `<top (required)>'
    from /usr/local/lib/ruby/gems/1.9.1/gems/railties-4.0.0/lib/rails/commands.rb:76:in `require'
    from /usr/local/lib/ruby/gems/1.9.1/gems/railties-4.0.0/lib/rails/commands.rb:76:in `block in <top (required)>'
    from /usr/local/lib/ruby/gems/1.9.1/gems/railties-4.0.0/lib/rails/commands.rb:73:in `tap'
    from /usr/local/lib/ruby/gems/1.9.1/gems/railties-4.0.0/lib/rails/commands.rb:73:in `<top (required)>'
    from bin/rails:4:in `require'
    from bin/rails:4:in `<main>'

我已经从源代码安装了mysql。安装地点：

$ whereis mysql mysql: /usr/local/mysql
我试着用gem用
安装mysql2——用mysql-config
，一切正常：

$ sudo gem install mysql2 -- --with-mysql-config=/usr/local/mysql/bin/mysql_config Building native extensions. This could take a while... Successfully installed mysql2-0.3.13 1 gem installed Installing ri documentation for mysql2-0.3.13... Installing RDoc documentation for mysql2-0.3.13...

这里是我的数据库.yml：

$ ls -al /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so -rwxr-xr-x 1 root root 131K Oct 7 00:31 /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so

development: adapter: mysql2 encoding: utf8 database: RailsBegin_development pool: 5 username: root password: passwd host: localhost socket: /tmp/mysql.sock

$ bundle install Using rake (10.1.0) Using i18n (0.6.5) Using minitest (4.7.5) Using multi_json (1.8.1) Using atomic (1.1.14) Using thread_safe (0.1.3) Using tzinfo (0.3.37) Using activesupport (4.0.0) Using builder (3.1.4) Using erubis (2.7.0) Using rack (1.5.2) Using rack-test (0.6.2) Using actionpack (4.0.0) Using mime-types (1.25) Using polyglot (0.3.3) Using treetop (1.4.15) Using mail (2.5.4) Using actionmailer (4.0.0) Using activemodel (4.0.0) Using activerecord-deprecated_finders (1.0.3) Using arel (4.0.0) Using activerecord (4.0.0) Using coffee-script-source (1.6.3) Using execjs (2.0.2) Using coffee-script (2.2.0) Using thor (0.18.1) Using railties (4.0.0) Using coffee-rails (4.0.0) Using hike (1.2.3) Using jbuilder (1.5.1) Using jquery-rails (3.0.4) Using json (1.8.0) Using mysql2 (0.3.13) Using bundler (1.3.5) Using tilt (1.4.1) Using sprockets (2.10.0) Using sprockets-rails (2.0.0) Using rails (4.0.0) Using rdoc (3.12.2) Using sass (3.2.12) Using sass-rails (4.0.0) Using sdoc (0.3.20) Using turbolinks (1.3.0) Using uglifier (2.2.1) Your bundle is complete! Use `bundle show [gemname]` to see where a bundled gem is installed.

$ sudo gem install mysql2 -v 0.3.11 -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin Fetching: mysql2-0.3.11.gem (100%) Building native extensions. This could take a while... Successfully installed mysql2-0.3.11 1 gem installed Installing ri documentation for mysql2-0.3.11... Installing RDoc documentation for mysql2-0.3.11...

gem 'mysql2', '~> 0.3.11'

$ bundle install Fetching gem metadata from https://rubygems.org/........... Fetching gem metadata from https://rubygems.org/.. Resolving dependencies... Using rake (10.1.0) Using i18n (0.6.5) Using minitest (4.7.5) Using multi_json (1.8.1) Using atomic (1.1.14) Using thread_safe (0.1.3) Using tzinfo (0.3.37) Using activesupport (4.0.0) Using builder (3.1.4) Using erubis (2.7.0) Using rack (1.5.2) Using rack-test (0.6.2) Using actionpack (4.0.0) Using mime-types (1.25) Using polyglot (0.3.3) Using treetop (1.4.15) Using mail (2.5.4) Using actionmailer (4.0.0) Using activemodel (4.0.0) Using activerecord-deprecated_finders (1.0.3) Using arel (4.0.0) Using activerecord (4.0.0) Using bundler (1.3.5) Using coffee-script-source (1.6.3) Using execjs (2.0.2) Using coffee-script (2.2.0) Using thor (0.18.1) Using railties (4.0.0) Using coffee-rails (4.0.0) Using hike (1.2.3) Using jbuilder (1.5.1) Using jquery-rails (3.0.4) Using json (1.8.0) Installing mysql2 (0.3.13) Using tilt (1.4.1) Using sprockets (2.10.0) Using sprockets-rails (2.0.0) Using rails (4.0.0) Using rdoc (3.12.2) Using sass (3.2.12) Using sass-rails (4.0.0) Using sdoc (0.3.20) Using turbolinks (1.3.0) Using uglifier (2.2.1) Your bundle is complete! Use `bundle show [gemname]` to see where a bundled gem is installed.

$ gem list | grep mysql2 mysql2 (0.3.13, 0.3.11)

$ ls -al total 160K -rw-r--r-- 1 mysql mysql 18K Sep 10 15:38 COPYING -rw-r--r-- 1 mysql mysql 2.5K Sep 10 15:38 README -rw-r--r-- 1 mysql mysql 87K Sep 10 15:38 INSTALL-BINARY drwxr-xr-x 2 mysql mysql 4.0K Oct 1 23:51 docs/ drwxr-xr-x 3 mysql mysql 4.0K Oct 1 23:51 include/ drwxr-xr-x 3 mysql mysql 4.0K Oct 1 23:51 lib/ drwxr-xr-x 10 mysql mysql 4.0K Oct 1 23:52 mysql-test/ drwxr-xr-x 28 mysql mysql 4.0K Oct 1 23:52 share/ drwxr-xr-x 2 mysql mysql 4.0K Oct 1 23:52 scripts/ drwxr-xr-x 4 mysql mysql 4.0K Oct 1 23:52 sql-bench/ drwxr-xr-x 4 mysql mysql 4.0K Oct 1 23:52 man/ drwxr-xr-x 3 mysql mysql 4.0K Oct 1 23:52 support-files/ -rw-r--r-- 1 mysql mysql 943 Oct 1 23:55 my.cnf drwxr-xr-x 2 mysql mysql 4.0K Oct 1 23:57 bin/ drwxr-xr-x 6 mysql mysql 4.0K Oct 7 01:04 data/

$ sudo gem uninstall mysql2 $ sudo gem install mysql2 -v 0.3.11 --platform=ruby -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin $ rm -rf Gemfile.lock $ bundle install

$ sudo apt-get install nodejs
以下是我的数据库：

mysql> SHOW DATABASES; +------------------------+ | Database | +------------------------+ | information_schema | | RailsBegin_development | | mysql | | performance_schema | | test | +------------------------+ 5 rows in set (0.00 sec)
这里是我的捆绑包安装：

$ ls -al /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so -rwxr-xr-x 1 root root 131K Oct 7 00:31 /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so

development: adapter: mysql2 encoding: utf8 database: RailsBegin_development pool: 5 username: root password: passwd host: localhost socket: /tmp/mysql.sock

$ bundle install Using rake (10.1.0) Using i18n (0.6.5) Using minitest (4.7.5) Using multi_json (1.8.1) Using atomic (1.1.14) Using thread_safe (0.1.3) Using tzinfo (0.3.37) Using activesupport (4.0.0) Using builder (3.1.4) Using erubis (2.7.0) Using rack (1.5.2) Using rack-test (0.6.2) Using actionpack (4.0.0) Using mime-types (1.25) Using polyglot (0.3.3) Using treetop (1.4.15) Using mail (2.5.4) Using actionmailer (4.0.0) Using activemodel (4.0.0) Using activerecord-deprecated_finders (1.0.3) Using arel (4.0.0) Using activerecord (4.0.0) Using coffee-script-source (1.6.3) Using execjs (2.0.2) Using coffee-script (2.2.0) Using thor (0.18.1) Using railties (4.0.0) Using coffee-rails (4.0.0) Using hike (1.2.3) Using jbuilder (1.5.1) Using jquery-rails (3.0.4) Using json (1.8.0) Using mysql2 (0.3.13) Using bundler (1.3.5) Using tilt (1.4.1) Using sprockets (2.10.0) Using sprockets-rails (2.0.0) Using rails (4.0.0) Using rdoc (3.12.2) Using sass (3.2.12) Using sass-rails (4.0.0) Using sdoc (0.3.20) Using turbolinks (1.3.0) Using uglifier (2.2.1) Your bundle is complete! Use `bundle show [gemname]` to see where a bundled gem is installed.

$ sudo gem install mysql2 -v 0.3.11 -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin Fetching: mysql2-0.3.11.gem (100%) Building native extensions. This could take a while... Successfully installed mysql2-0.3.11 1 gem installed Installing ri documentation for mysql2-0.3.11... Installing RDoc documentation for mysql2-0.3.11...

gem 'mysql2', '~> 0.3.11'

$ bundle install Fetching gem metadata from https://rubygems.org/........... Fetching gem metadata from https://rubygems.org/.. Resolving dependencies... Using rake (10.1.0) Using i18n (0.6.5) Using minitest (4.7.5) Using multi_json (1.8.1) Using atomic (1.1.14) Using thread_safe (0.1.3) Using tzinfo (0.3.37) Using activesupport (4.0.0) Using builder (3.1.4) Using erubis (2.7.0) Using rack (1.5.2) Using rack-test (0.6.2) Using actionpack (4.0.0) Using mime-types (1.25) Using polyglot (0.3.3) Using treetop (1.4.15) Using mail (2.5.4) Using actionmailer (4.0.0) Using activemodel (4.0.0) Using activerecord-deprecated_finders (1.0.3) Using arel (4.0.0) Using activerecord (4.0.0) Using bundler (1.3.5) Using coffee-script-source (1.6.3) Using execjs (2.0.2) Using coffee-script (2.2.0) Using thor (0.18.1) Using railties (4.0.0) Using coffee-rails (4.0.0) Using hike (1.2.3) Using jbuilder (1.5.1) Using jquery-rails (3.0.4) Using json (1.8.0) Installing mysql2 (0.3.13) Using tilt (1.4.1) Using sprockets (2.10.0) Using sprockets-rails (2.0.0) Using rails (4.0.0) Using rdoc (3.12.2) Using sass (3.2.12) Using sass-rails (4.0.0) Using sdoc (0.3.20) Using turbolinks (1.3.0) Using uglifier (2.2.1) Your bundle is complete! Use `bundle show [gemname]` to see where a bundled gem is installed.

$ gem list | grep mysql2 mysql2 (0.3.13, 0.3.11)

$ ls -al total 160K -rw-r--r-- 1 mysql mysql 18K Sep 10 15:38 COPYING -rw-r--r-- 1 mysql mysql 2.5K Sep 10 15:38 README -rw-r--r-- 1 mysql mysql 87K Sep 10 15:38 INSTALL-BINARY drwxr-xr-x 2 mysql mysql 4.0K Oct 1 23:51 docs/ drwxr-xr-x 3 mysql mysql 4.0K Oct 1 23:51 include/ drwxr-xr-x 3 mysql mysql 4.0K Oct 1 23:51 lib/ drwxr-xr-x 10 mysql mysql 4.0K Oct 1 23:52 mysql-test/ drwxr-xr-x 28 mysql mysql 4.0K Oct 1 23:52 share/ drwxr-xr-x 2 mysql mysql 4.0K Oct 1 23:52 scripts/ drwxr-xr-x 4 mysql mysql 4.0K Oct 1 23:52 sql-bench/ drwxr-xr-x 4 mysql mysql 4.0K Oct 1 23:52 man/ drwxr-xr-x 3 mysql mysql 4.0K Oct 1 23:52 support-files/ -rw-r--r-- 1 mysql mysql 943 Oct 1 23:55 my.cnf drwxr-xr-x 2 mysql mysql 4.0K Oct 1 23:57 bin/ drwxr-xr-x 6 mysql mysql 4.0K Oct 7 01:04 data/

$ sudo gem uninstall mysql2 $ sudo gem install mysql2 -v 0.3.11 --platform=ruby -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin $ rm -rf Gemfile.lock $ bundle install

$ sudo apt-get install nodejs
我不知道它怎么了。大家都能帮我吗？提前谢谢
============
更新1 我已卸载mysql2并重新安装为0.3.11：

$ ls -al /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so -rwxr-xr-x 1 root root 131K Oct 7 00:31 /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so

development: adapter: mysql2 encoding: utf8 database: RailsBegin_development pool: 5 username: root password: passwd host: localhost socket: /tmp/mysql.sock

$ bundle install Using rake (10.1.0) Using i18n (0.6.5) Using minitest (4.7.5) Using multi_json (1.8.1) Using atomic (1.1.14) Using thread_safe (0.1.3) Using tzinfo (0.3.37) Using activesupport (4.0.0) Using builder (3.1.4) Using erubis (2.7.0) Using rack (1.5.2) Using rack-test (0.6.2) Using actionpack (4.0.0) Using mime-types (1.25) Using polyglot (0.3.3) Using treetop (1.4.15) Using mail (2.5.4) Using actionmailer (4.0.0) Using activemodel (4.0.0) Using activerecord-deprecated_finders (1.0.3) Using arel (4.0.0) Using activerecord (4.0.0) Using coffee-script-source (1.6.3) Using execjs (2.0.2) Using coffee-script (2.2.0) Using thor (0.18.1) Using railties (4.0.0) Using coffee-rails (4.0.0) Using hike (1.2.3) Using jbuilder (1.5.1) Using jquery-rails (3.0.4) Using json (1.8.0) Using mysql2 (0.3.13) Using bundler (1.3.5) Using tilt (1.4.1) Using sprockets (2.10.0) Using sprockets-rails (2.0.0) Using rails (4.0.0) Using rdoc (3.12.2) Using sass (3.2.12) Using sass-rails (4.0.0) Using sdoc (0.3.20) Using turbolinks (1.3.0) Using uglifier (2.2.1) Your bundle is complete! Use `bundle show [gemname]` to see where a bundled gem is installed.

$ sudo gem install mysql2 -v 0.3.11 -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin Fetching: mysql2-0.3.11.gem (100%) Building native extensions. This could take a while... Successfully installed mysql2-0.3.11 1 gem installed Installing ri documentation for mysql2-0.3.11... Installing RDoc documentation for mysql2-0.3.11...

gem 'mysql2', '~> 0.3.11'

$ bundle install Fetching gem metadata from https://rubygems.org/........... Fetching gem metadata from https://rubygems.org/.. Resolving dependencies... Using rake (10.1.0) Using i18n (0.6.5) Using minitest (4.7.5) Using multi_json (1.8.1) Using atomic (1.1.14) Using thread_safe (0.1.3) Using tzinfo (0.3.37) Using activesupport (4.0.0) Using builder (3.1.4) Using erubis (2.7.0) Using rack (1.5.2) Using rack-test (0.6.2) Using actionpack (4.0.0) Using mime-types (1.25) Using polyglot (0.3.3) Using treetop (1.4.15) Using mail (2.5.4) Using actionmailer (4.0.0) Using activemodel (4.0.0) Using activerecord-deprecated_finders (1.0.3) Using arel (4.0.0) Using activerecord (4.0.0) Using bundler (1.3.5) Using coffee-script-source (1.6.3) Using execjs (2.0.2) Using coffee-script (2.2.0) Using thor (0.18.1) Using railties (4.0.0) Using coffee-rails (4.0.0) Using hike (1.2.3) Using jbuilder (1.5.1) Using jquery-rails (3.0.4) Using json (1.8.0) Installing mysql2 (0.3.13) Using tilt (1.4.1) Using sprockets (2.10.0) Using sprockets-rails (2.0.0) Using rails (4.0.0) Using rdoc (3.12.2) Using sass (3.2.12) Using sass-rails (4.0.0) Using sdoc (0.3.20) Using turbolinks (1.3.0) Using uglifier (2.2.1) Your bundle is complete! Use `bundle show [gemname]` to see where a bundled gem is installed.

$ gem list | grep mysql2 mysql2 (0.3.13, 0.3.11)

$ ls -al total 160K -rw-r--r-- 1 mysql mysql 18K Sep 10 15:38 COPYING -rw-r--r-- 1 mysql mysql 2.5K Sep 10 15:38 README -rw-r--r-- 1 mysql mysql 87K Sep 10 15:38 INSTALL-BINARY drwxr-xr-x 2 mysql mysql 4.0K Oct 1 23:51 docs/ drwxr-xr-x 3 mysql mysql 4.0K Oct 1 23:51 include/ drwxr-xr-x 3 mysql mysql 4.0K Oct 1 23:51 lib/ drwxr-xr-x 10 mysql mysql 4.0K Oct 1 23:52 mysql-test/ drwxr-xr-x 28 mysql mysql 4.0K Oct 1 23:52 share/ drwxr-xr-x 2 mysql mysql 4.0K Oct 1 23:52 scripts/ drwxr-xr-x 4 mysql mysql 4.0K Oct 1 23:52 sql-bench/ drwxr-xr-x 4 mysql mysql 4.0K Oct 1 23:52 man/ drwxr-xr-x 3 mysql mysql 4.0K Oct 1 23:52 support-files/ -rw-r--r-- 1 mysql mysql 943 Oct 1 23:55 my.cnf drwxr-xr-x 2 mysql mysql 4.0K Oct 1 23:57 bin/ drwxr-xr-x 6 mysql mysql 4.0K Oct 7 01:04 data/

$ sudo gem uninstall mysql2 $ sudo gem install mysql2 -v 0.3.11 --platform=ruby -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin $ rm -rf Gemfile.lock $ bundle install

$ sudo apt-get install nodejs
并更新Gemfile：

 $ ls -al /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so
-rwxr-xr-x 1 root root 131K Oct  7 00:31 /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so

development:
  adapter: mysql2
  encoding: utf8
  database: RailsBegin_development
  pool: 5
  username: root
  password: passwd
  host: localhost
  socket: /tmp/mysql.sock

$ bundle install
Using rake (10.1.0) 
Using i18n (0.6.5) 
Using minitest (4.7.5) 
Using multi_json (1.8.1) 
Using atomic (1.1.14) 
Using thread_safe (0.1.3) 
Using tzinfo (0.3.37) 
Using activesupport (4.0.0) 
Using builder (3.1.4) 
Using erubis (2.7.0) 
Using rack (1.5.2) 
Using rack-test (0.6.2) 
Using actionpack (4.0.0) 
Using mime-types (1.25) 
Using polyglot (0.3.3) 
Using treetop (1.4.15) 
Using mail (2.5.4) 
Using actionmailer (4.0.0) 
Using activemodel (4.0.0) 
Using activerecord-deprecated_finders (1.0.3) 
Using arel (4.0.0) 
Using activerecord (4.0.0) 
Using coffee-script-source (1.6.3) 
Using execjs (2.0.2) 
Using coffee-script (2.2.0) 
Using thor (0.18.1) 
Using railties (4.0.0) 
Using coffee-rails (4.0.0) 
Using hike (1.2.3) 
Using jbuilder (1.5.1) 
Using jquery-rails (3.0.4) 
Using json (1.8.0) 
Using mysql2 (0.3.13) 
Using bundler (1.3.5) 
Using tilt (1.4.1) 
Using sprockets (2.10.0) 
Using sprockets-rails (2.0.0) 
Using rails (4.0.0) 
Using rdoc (3.12.2) 
Using sass (3.2.12) 
Using sass-rails (4.0.0) 
Using sdoc (0.3.20) 
Using turbolinks (1.3.0) 
Using uglifier (2.2.1) 
Your bundle is complete!
Use `bundle show [gemname]` to see where a bundled gem is installed.

$ sudo gem install mysql2 -v 0.3.11 -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin
Fetching: mysql2-0.3.11.gem (100%)
Building native extensions.  This could take a while...
Successfully installed mysql2-0.3.11
1 gem installed
Installing ri documentation for mysql2-0.3.11...
Installing RDoc documentation for mysql2-0.3.11...

gem 'mysql2', '~> 0.3.11'

$ bundle install
Fetching gem metadata from https://rubygems.org/...........
Fetching gem metadata from https://rubygems.org/..
Resolving dependencies...
Using rake (10.1.0) 
Using i18n (0.6.5) 
Using minitest (4.7.5) 
Using multi_json (1.8.1) 
Using atomic (1.1.14) 
Using thread_safe (0.1.3) 
Using tzinfo (0.3.37) 
Using activesupport (4.0.0) 
Using builder (3.1.4) 
Using erubis (2.7.0) 
Using rack (1.5.2) 
Using rack-test (0.6.2) 
Using actionpack (4.0.0) 
Using mime-types (1.25) 
Using polyglot (0.3.3) 
Using treetop (1.4.15) 
Using mail (2.5.4) 
Using actionmailer (4.0.0) 
Using activemodel (4.0.0) 
Using activerecord-deprecated_finders (1.0.3) 
Using arel (4.0.0) 
Using activerecord (4.0.0) 
Using bundler (1.3.5) 
Using coffee-script-source (1.6.3) 
Using execjs (2.0.2) 
Using coffee-script (2.2.0) 
Using thor (0.18.1) 
Using railties (4.0.0) 
Using coffee-rails (4.0.0) 
Using hike (1.2.3) 
Using jbuilder (1.5.1) 
Using jquery-rails (3.0.4) 
Using json (1.8.0) 
Installing mysql2 (0.3.13) 
Using tilt (1.4.1) 
Using sprockets (2.10.0) 
Using sprockets-rails (2.0.0) 
Using rails (4.0.0) 
Using rdoc (3.12.2) 
Using sass (3.2.12) 
Using sass-rails (4.0.0) 
Using sdoc (0.3.20) 
Using turbolinks (1.3.0) 
Using uglifier (2.2.1) 
Your bundle is complete!
Use `bundle show [gemname]` to see where a bundled gem is installed.

$ gem list | grep mysql2
mysql2 (0.3.13, 0.3.11)

$ ls -al
total 160K
-rw-r--r--  1 mysql mysql  18K Sep 10 15:38 COPYING
-rw-r--r--  1 mysql mysql 2.5K Sep 10 15:38 README
-rw-r--r--  1 mysql mysql  87K Sep 10 15:38 INSTALL-BINARY
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:51 docs/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:51 include/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:51 lib/
drwxr-xr-x 10 mysql mysql 4.0K Oct  1 23:52 mysql-test/
drwxr-xr-x 28 mysql mysql 4.0K Oct  1 23:52 share/
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:52 scripts/
drwxr-xr-x  4 mysql mysql 4.0K Oct  1 23:52 sql-bench/
drwxr-xr-x  4 mysql mysql 4.0K Oct  1 23:52 man/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:52 support-files/
-rw-r--r--  1 mysql mysql  943 Oct  1 23:55 my.cnf
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:57 bin/
drwxr-xr-x  6 mysql mysql 4.0K Oct  7 01:04 data/

$ sudo gem uninstall mysql2
$ sudo gem install mysql2 -v 0.3.11 --platform=ruby -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin
$ rm -rf Gemfile.lock
$ bundle install

$ sudo apt-get install nodejs

和捆绑安装再次安装，但仍将安装0.3.13：

 $ ls -al /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so
-rwxr-xr-x 1 root root 131K Oct  7 00:31 /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so

development:
  adapter: mysql2
  encoding: utf8
  database: RailsBegin_development
  pool: 5
  username: root
  password: passwd
  host: localhost
  socket: /tmp/mysql.sock

$ bundle install
Using rake (10.1.0) 
Using i18n (0.6.5) 
Using minitest (4.7.5) 
Using multi_json (1.8.1) 
Using atomic (1.1.14) 
Using thread_safe (0.1.3) 
Using tzinfo (0.3.37) 
Using activesupport (4.0.0) 
Using builder (3.1.4) 
Using erubis (2.7.0) 
Using rack (1.5.2) 
Using rack-test (0.6.2) 
Using actionpack (4.0.0) 
Using mime-types (1.25) 
Using polyglot (0.3.3) 
Using treetop (1.4.15) 
Using mail (2.5.4) 
Using actionmailer (4.0.0) 
Using activemodel (4.0.0) 
Using activerecord-deprecated_finders (1.0.3) 
Using arel (4.0.0) 
Using activerecord (4.0.0) 
Using coffee-script-source (1.6.3) 
Using execjs (2.0.2) 
Using coffee-script (2.2.0) 
Using thor (0.18.1) 
Using railties (4.0.0) 
Using coffee-rails (4.0.0) 
Using hike (1.2.3) 
Using jbuilder (1.5.1) 
Using jquery-rails (3.0.4) 
Using json (1.8.0) 
Using mysql2 (0.3.13) 
Using bundler (1.3.5) 
Using tilt (1.4.1) 
Using sprockets (2.10.0) 
Using sprockets-rails (2.0.0) 
Using rails (4.0.0) 
Using rdoc (3.12.2) 
Using sass (3.2.12) 
Using sass-rails (4.0.0) 
Using sdoc (0.3.20) 
Using turbolinks (1.3.0) 
Using uglifier (2.2.1) 
Your bundle is complete!
Use `bundle show [gemname]` to see where a bundled gem is installed.

$ sudo gem install mysql2 -v 0.3.11 -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin
Fetching: mysql2-0.3.11.gem (100%)
Building native extensions.  This could take a while...
Successfully installed mysql2-0.3.11
1 gem installed
Installing ri documentation for mysql2-0.3.11...
Installing RDoc documentation for mysql2-0.3.11...

gem 'mysql2', '~> 0.3.11'

$ bundle install
Fetching gem metadata from https://rubygems.org/...........
Fetching gem metadata from https://rubygems.org/..
Resolving dependencies...
Using rake (10.1.0) 
Using i18n (0.6.5) 
Using minitest (4.7.5) 
Using multi_json (1.8.1) 
Using atomic (1.1.14) 
Using thread_safe (0.1.3) 
Using tzinfo (0.3.37) 
Using activesupport (4.0.0) 
Using builder (3.1.4) 
Using erubis (2.7.0) 
Using rack (1.5.2) 
Using rack-test (0.6.2) 
Using actionpack (4.0.0) 
Using mime-types (1.25) 
Using polyglot (0.3.3) 
Using treetop (1.4.15) 
Using mail (2.5.4) 
Using actionmailer (4.0.0) 
Using activemodel (4.0.0) 
Using activerecord-deprecated_finders (1.0.3) 
Using arel (4.0.0) 
Using activerecord (4.0.0) 
Using bundler (1.3.5) 
Using coffee-script-source (1.6.3) 
Using execjs (2.0.2) 
Using coffee-script (2.2.0) 
Using thor (0.18.1) 
Using railties (4.0.0) 
Using coffee-rails (4.0.0) 
Using hike (1.2.3) 
Using jbuilder (1.5.1) 
Using jquery-rails (3.0.4) 
Using json (1.8.0) 
Installing mysql2 (0.3.13) 
Using tilt (1.4.1) 
Using sprockets (2.10.0) 
Using sprockets-rails (2.0.0) 
Using rails (4.0.0) 
Using rdoc (3.12.2) 
Using sass (3.2.12) 
Using sass-rails (4.0.0) 
Using sdoc (0.3.20) 
Using turbolinks (1.3.0) 
Using uglifier (2.2.1) 
Your bundle is complete!
Use `bundle show [gemname]` to see where a bundled gem is installed.

$ gem list | grep mysql2
mysql2 (0.3.13, 0.3.11)

$ ls -al
total 160K
-rw-r--r--  1 mysql mysql  18K Sep 10 15:38 COPYING
-rw-r--r--  1 mysql mysql 2.5K Sep 10 15:38 README
-rw-r--r--  1 mysql mysql  87K Sep 10 15:38 INSTALL-BINARY
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:51 docs/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:51 include/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:51 lib/
drwxr-xr-x 10 mysql mysql 4.0K Oct  1 23:52 mysql-test/
drwxr-xr-x 28 mysql mysql 4.0K Oct  1 23:52 share/
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:52 scripts/
drwxr-xr-x  4 mysql mysql 4.0K Oct  1 23:52 sql-bench/
drwxr-xr-x  4 mysql mysql 4.0K Oct  1 23:52 man/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:52 support-files/
-rw-r--r--  1 mysql mysql  943 Oct  1 23:55 my.cnf
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:57 bin/
drwxr-xr-x  6 mysql mysql 4.0K Oct  7 01:04 data/

$ sudo gem uninstall mysql2
$ sudo gem install mysql2 -v 0.3.11 --platform=ruby -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin
$ rm -rf Gemfile.lock
$ bundle install

$ sudo apt-get install nodejs

此处宝石列表：

 $ ls -al /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so
-rwxr-xr-x 1 root root 131K Oct  7 00:31 /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so

development:
  adapter: mysql2
  encoding: utf8
  database: RailsBegin_development
  pool: 5
  username: root
  password: passwd
  host: localhost
  socket: /tmp/mysql.sock

$ bundle install
Using rake (10.1.0) 
Using i18n (0.6.5) 
Using minitest (4.7.5) 
Using multi_json (1.8.1) 
Using atomic (1.1.14) 
Using thread_safe (0.1.3) 
Using tzinfo (0.3.37) 
Using activesupport (4.0.0) 
Using builder (3.1.4) 
Using erubis (2.7.0) 
Using rack (1.5.2) 
Using rack-test (0.6.2) 
Using actionpack (4.0.0) 
Using mime-types (1.25) 
Using polyglot (0.3.3) 
Using treetop (1.4.15) 
Using mail (2.5.4) 
Using actionmailer (4.0.0) 
Using activemodel (4.0.0) 
Using activerecord-deprecated_finders (1.0.3) 
Using arel (4.0.0) 
Using activerecord (4.0.0) 
Using coffee-script-source (1.6.3) 
Using execjs (2.0.2) 
Using coffee-script (2.2.0) 
Using thor (0.18.1) 
Using railties (4.0.0) 
Using coffee-rails (4.0.0) 
Using hike (1.2.3) 
Using jbuilder (1.5.1) 
Using jquery-rails (3.0.4) 
Using json (1.8.0) 
Using mysql2 (0.3.13) 
Using bundler (1.3.5) 
Using tilt (1.4.1) 
Using sprockets (2.10.0) 
Using sprockets-rails (2.0.0) 
Using rails (4.0.0) 
Using rdoc (3.12.2) 
Using sass (3.2.12) 
Using sass-rails (4.0.0) 
Using sdoc (0.3.20) 
Using turbolinks (1.3.0) 
Using uglifier (2.2.1) 
Your bundle is complete!
Use `bundle show [gemname]` to see where a bundled gem is installed.

$ sudo gem install mysql2 -v 0.3.11 -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin
Fetching: mysql2-0.3.11.gem (100%)
Building native extensions.  This could take a while...
Successfully installed mysql2-0.3.11
1 gem installed
Installing ri documentation for mysql2-0.3.11...
Installing RDoc documentation for mysql2-0.3.11...

gem 'mysql2', '~> 0.3.11'

$ bundle install
Fetching gem metadata from https://rubygems.org/...........
Fetching gem metadata from https://rubygems.org/..
Resolving dependencies...
Using rake (10.1.0) 
Using i18n (0.6.5) 
Using minitest (4.7.5) 
Using multi_json (1.8.1) 
Using atomic (1.1.14) 
Using thread_safe (0.1.3) 
Using tzinfo (0.3.37) 
Using activesupport (4.0.0) 
Using builder (3.1.4) 
Using erubis (2.7.0) 
Using rack (1.5.2) 
Using rack-test (0.6.2) 
Using actionpack (4.0.0) 
Using mime-types (1.25) 
Using polyglot (0.3.3) 
Using treetop (1.4.15) 
Using mail (2.5.4) 
Using actionmailer (4.0.0) 
Using activemodel (4.0.0) 
Using activerecord-deprecated_finders (1.0.3) 
Using arel (4.0.0) 
Using activerecord (4.0.0) 
Using bundler (1.3.5) 
Using coffee-script-source (1.6.3) 
Using execjs (2.0.2) 
Using coffee-script (2.2.0) 
Using thor (0.18.1) 
Using railties (4.0.0) 
Using coffee-rails (4.0.0) 
Using hike (1.2.3) 
Using jbuilder (1.5.1) 
Using jquery-rails (3.0.4) 
Using json (1.8.0) 
Installing mysql2 (0.3.13) 
Using tilt (1.4.1) 
Using sprockets (2.10.0) 
Using sprockets-rails (2.0.0) 
Using rails (4.0.0) 
Using rdoc (3.12.2) 
Using sass (3.2.12) 
Using sass-rails (4.0.0) 
Using sdoc (0.3.20) 
Using turbolinks (1.3.0) 
Using uglifier (2.2.1) 
Your bundle is complete!
Use `bundle show [gemname]` to see where a bundled gem is installed.

$ gem list | grep mysql2
mysql2 (0.3.13, 0.3.11)

$ ls -al
total 160K
-rw-r--r--  1 mysql mysql  18K Sep 10 15:38 COPYING
-rw-r--r--  1 mysql mysql 2.5K Sep 10 15:38 README
-rw-r--r--  1 mysql mysql  87K Sep 10 15:38 INSTALL-BINARY
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:51 docs/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:51 include/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:51 lib/
drwxr-xr-x 10 mysql mysql 4.0K Oct  1 23:52 mysql-test/
drwxr-xr-x 28 mysql mysql 4.0K Oct  1 23:52 share/
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:52 scripts/
drwxr-xr-x  4 mysql mysql 4.0K Oct  1 23:52 sql-bench/
drwxr-xr-x  4 mysql mysql 4.0K Oct  1 23:52 man/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:52 support-files/
-rw-r--r--  1 mysql mysql  943 Oct  1 23:55 my.cnf
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:57 bin/
drwxr-xr-x  6 mysql mysql 4.0K Oct  7 01:04 data/

$ sudo gem uninstall mysql2
$ sudo gem install mysql2 -v 0.3.11 --platform=ruby -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin
$ rm -rf Gemfile.lock
$ bundle install

$ sudo apt-get install nodejs

顺便说一下，mysql（通过源代码安装）的所有者是mysql：

 $ ls -al /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so
-rwxr-xr-x 1 root root 131K Oct  7 00:31 /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so

development:
  adapter: mysql2
  encoding: utf8
  database: RailsBegin_development
  pool: 5
  username: root
  password: passwd
  host: localhost
  socket: /tmp/mysql.sock

$ bundle install
Using rake (10.1.0) 
Using i18n (0.6.5) 
Using minitest (4.7.5) 
Using multi_json (1.8.1) 
Using atomic (1.1.14) 
Using thread_safe (0.1.3) 
Using tzinfo (0.3.37) 
Using activesupport (4.0.0) 
Using builder (3.1.4) 
Using erubis (2.7.0) 
Using rack (1.5.2) 
Using rack-test (0.6.2) 
Using actionpack (4.0.0) 
Using mime-types (1.25) 
Using polyglot (0.3.3) 
Using treetop (1.4.15) 
Using mail (2.5.4) 
Using actionmailer (4.0.0) 
Using activemodel (4.0.0) 
Using activerecord-deprecated_finders (1.0.3) 
Using arel (4.0.0) 
Using activerecord (4.0.0) 
Using coffee-script-source (1.6.3) 
Using execjs (2.0.2) 
Using coffee-script (2.2.0) 
Using thor (0.18.1) 
Using railties (4.0.0) 
Using coffee-rails (4.0.0) 
Using hike (1.2.3) 
Using jbuilder (1.5.1) 
Using jquery-rails (3.0.4) 
Using json (1.8.0) 
Using mysql2 (0.3.13) 
Using bundler (1.3.5) 
Using tilt (1.4.1) 
Using sprockets (2.10.0) 
Using sprockets-rails (2.0.0) 
Using rails (4.0.0) 
Using rdoc (3.12.2) 
Using sass (3.2.12) 
Using sass-rails (4.0.0) 
Using sdoc (0.3.20) 
Using turbolinks (1.3.0) 
Using uglifier (2.2.1) 
Your bundle is complete!
Use `bundle show [gemname]` to see where a bundled gem is installed.

$ sudo gem install mysql2 -v 0.3.11 -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin
Fetching: mysql2-0.3.11.gem (100%)
Building native extensions.  This could take a while...
Successfully installed mysql2-0.3.11
1 gem installed
Installing ri documentation for mysql2-0.3.11...
Installing RDoc documentation for mysql2-0.3.11...

gem 'mysql2', '~> 0.3.11'

$ bundle install
Fetching gem metadata from https://rubygems.org/...........
Fetching gem metadata from https://rubygems.org/..
Resolving dependencies...
Using rake (10.1.0) 
Using i18n (0.6.5) 
Using minitest (4.7.5) 
Using multi_json (1.8.1) 
Using atomic (1.1.14) 
Using thread_safe (0.1.3) 
Using tzinfo (0.3.37) 
Using activesupport (4.0.0) 
Using builder (3.1.4) 
Using erubis (2.7.0) 
Using rack (1.5.2) 
Using rack-test (0.6.2) 
Using actionpack (4.0.0) 
Using mime-types (1.25) 
Using polyglot (0.3.3) 
Using treetop (1.4.15) 
Using mail (2.5.4) 
Using actionmailer (4.0.0) 
Using activemodel (4.0.0) 
Using activerecord-deprecated_finders (1.0.3) 
Using arel (4.0.0) 
Using activerecord (4.0.0) 
Using bundler (1.3.5) 
Using coffee-script-source (1.6.3) 
Using execjs (2.0.2) 
Using coffee-script (2.2.0) 
Using thor (0.18.1) 
Using railties (4.0.0) 
Using coffee-rails (4.0.0) 
Using hike (1.2.3) 
Using jbuilder (1.5.1) 
Using jquery-rails (3.0.4) 
Using json (1.8.0) 
Installing mysql2 (0.3.13) 
Using tilt (1.4.1) 
Using sprockets (2.10.0) 
Using sprockets-rails (2.0.0) 
Using rails (4.0.0) 
Using rdoc (3.12.2) 
Using sass (3.2.12) 
Using sass-rails (4.0.0) 
Using sdoc (0.3.20) 
Using turbolinks (1.3.0) 
Using uglifier (2.2.1) 
Your bundle is complete!
Use `bundle show [gemname]` to see where a bundled gem is installed.

$ gem list | grep mysql2
mysql2 (0.3.13, 0.3.11)

$ ls -al
total 160K
-rw-r--r--  1 mysql mysql  18K Sep 10 15:38 COPYING
-rw-r--r--  1 mysql mysql 2.5K Sep 10 15:38 README
-rw-r--r--  1 mysql mysql  87K Sep 10 15:38 INSTALL-BINARY
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:51 docs/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:51 include/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:51 lib/
drwxr-xr-x 10 mysql mysql 4.0K Oct  1 23:52 mysql-test/
drwxr-xr-x 28 mysql mysql 4.0K Oct  1 23:52 share/
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:52 scripts/
drwxr-xr-x  4 mysql mysql 4.0K Oct  1 23:52 sql-bench/
drwxr-xr-x  4 mysql mysql 4.0K Oct  1 23:52 man/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:52 support-files/
-rw-r--r--  1 mysql mysql  943 Oct  1 23:55 my.cnf
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:57 bin/
drwxr-xr-x  6 mysql mysql 4.0K Oct  7 01:04 data/

$ sudo gem uninstall mysql2
$ sudo gem install mysql2 -v 0.3.11 --platform=ruby -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin
$ rm -rf Gemfile.lock
$ bundle install

$ sudo apt-get install nodejs

但是，ruby的所有者是root

这是因为权限问题吗

====================

更新2 安装mysql2版本：0.3.11，使用--platform=ruby：

 $ ls -al /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so
-rwxr-xr-x 1 root root 131K Oct  7 00:31 /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so

development:
  adapter: mysql2
  encoding: utf8
  database: RailsBegin_development
  pool: 5
  username: root
  password: passwd
  host: localhost
  socket: /tmp/mysql.sock

$ bundle install
Using rake (10.1.0) 
Using i18n (0.6.5) 
Using minitest (4.7.5) 
Using multi_json (1.8.1) 
Using atomic (1.1.14) 
Using thread_safe (0.1.3) 
Using tzinfo (0.3.37) 
Using activesupport (4.0.0) 
Using builder (3.1.4) 
Using erubis (2.7.0) 
Using rack (1.5.2) 
Using rack-test (0.6.2) 
Using actionpack (4.0.0) 
Using mime-types (1.25) 
Using polyglot (0.3.3) 
Using treetop (1.4.15) 
Using mail (2.5.4) 
Using actionmailer (4.0.0) 
Using activemodel (4.0.0) 
Using activerecord-deprecated_finders (1.0.3) 
Using arel (4.0.0) 
Using activerecord (4.0.0) 
Using coffee-script-source (1.6.3) 
Using execjs (2.0.2) 
Using coffee-script (2.2.0) 
Using thor (0.18.1) 
Using railties (4.0.0) 
Using coffee-rails (4.0.0) 
Using hike (1.2.3) 
Using jbuilder (1.5.1) 
Using jquery-rails (3.0.4) 
Using json (1.8.0) 
Using mysql2 (0.3.13) 
Using bundler (1.3.5) 
Using tilt (1.4.1) 
Using sprockets (2.10.0) 
Using sprockets-rails (2.0.0) 
Using rails (4.0.0) 
Using rdoc (3.12.2) 
Using sass (3.2.12) 
Using sass-rails (4.0.0) 
Using sdoc (0.3.20) 
Using turbolinks (1.3.0) 
Using uglifier (2.2.1) 
Your bundle is complete!
Use `bundle show [gemname]` to see where a bundled gem is installed.

$ sudo gem install mysql2 -v 0.3.11 -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin
Fetching: mysql2-0.3.11.gem (100%)
Building native extensions.  This could take a while...
Successfully installed mysql2-0.3.11
1 gem installed
Installing ri documentation for mysql2-0.3.11...
Installing RDoc documentation for mysql2-0.3.11...

gem 'mysql2', '~> 0.3.11'

$ bundle install
Fetching gem metadata from https://rubygems.org/...........
Fetching gem metadata from https://rubygems.org/..
Resolving dependencies...
Using rake (10.1.0) 
Using i18n (0.6.5) 
Using minitest (4.7.5) 
Using multi_json (1.8.1) 
Using atomic (1.1.14) 
Using thread_safe (0.1.3) 
Using tzinfo (0.3.37) 
Using activesupport (4.0.0) 
Using builder (3.1.4) 
Using erubis (2.7.0) 
Using rack (1.5.2) 
Using rack-test (0.6.2) 
Using actionpack (4.0.0) 
Using mime-types (1.25) 
Using polyglot (0.3.3) 
Using treetop (1.4.15) 
Using mail (2.5.4) 
Using actionmailer (4.0.0) 
Using activemodel (4.0.0) 
Using activerecord-deprecated_finders (1.0.3) 
Using arel (4.0.0) 
Using activerecord (4.0.0) 
Using bundler (1.3.5) 
Using coffee-script-source (1.6.3) 
Using execjs (2.0.2) 
Using coffee-script (2.2.0) 
Using thor (0.18.1) 
Using railties (4.0.0) 
Using coffee-rails (4.0.0) 
Using hike (1.2.3) 
Using jbuilder (1.5.1) 
Using jquery-rails (3.0.4) 
Using json (1.8.0) 
Installing mysql2 (0.3.13) 
Using tilt (1.4.1) 
Using sprockets (2.10.0) 
Using sprockets-rails (2.0.0) 
Using rails (4.0.0) 
Using rdoc (3.12.2) 
Using sass (3.2.12) 
Using sass-rails (4.0.0) 
Using sdoc (0.3.20) 
Using turbolinks (1.3.0) 
Using uglifier (2.2.1) 
Your bundle is complete!
Use `bundle show [gemname]` to see where a bundled gem is installed.

$ gem list | grep mysql2
mysql2 (0.3.13, 0.3.11)

$ ls -al
total 160K
-rw-r--r--  1 mysql mysql  18K Sep 10 15:38 COPYING
-rw-r--r--  1 mysql mysql 2.5K Sep 10 15:38 README
-rw-r--r--  1 mysql mysql  87K Sep 10 15:38 INSTALL-BINARY
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:51 docs/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:51 include/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:51 lib/
drwxr-xr-x 10 mysql mysql 4.0K Oct  1 23:52 mysql-test/
drwxr-xr-x 28 mysql mysql 4.0K Oct  1 23:52 share/
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:52 scripts/
drwxr-xr-x  4 mysql mysql 4.0K Oct  1 23:52 sql-bench/
drwxr-xr-x  4 mysql mysql 4.0K Oct  1 23:52 man/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:52 support-files/
-rw-r--r--  1 mysql mysql  943 Oct  1 23:55 my.cnf
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:57 bin/
drwxr-xr-x  6 mysql mysql 4.0K Oct  7 01:04 data/

$ sudo gem uninstall mysql2
$ sudo gem install mysql2 -v 0.3.11 --platform=ruby -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin
$ rm -rf Gemfile.lock
$ bundle install

$ sudo apt-get install nodejs

mysql变量可以通过以下方式找到：

$ mysqladmin variables
并且，安装NodeJS：

 $ ls -al /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so
-rwxr-xr-x 1 root root 131K Oct  7 00:31 /usr/local/lib/ruby/gems/1.9.1/gems/mysql2-0.3.13/lib/mysql2/mysql2.so

development:
  adapter: mysql2
  encoding: utf8
  database: RailsBegin_development
  pool: 5
  username: root
  password: passwd
  host: localhost
  socket: /tmp/mysql.sock

$ bundle install
Using rake (10.1.0) 
Using i18n (0.6.5) 
Using minitest (4.7.5) 
Using multi_json (1.8.1) 
Using atomic (1.1.14) 
Using thread_safe (0.1.3) 
Using tzinfo (0.3.37) 
Using activesupport (4.0.0) 
Using builder (3.1.4) 
Using erubis (2.7.0) 
Using rack (1.5.2) 
Using rack-test (0.6.2) 
Using actionpack (4.0.0) 
Using mime-types (1.25) 
Using polyglot (0.3.3) 
Using treetop (1.4.15) 
Using mail (2.5.4) 
Using actionmailer (4.0.0) 
Using activemodel (4.0.0) 
Using activerecord-deprecated_finders (1.0.3) 
Using arel (4.0.0) 
Using activerecord (4.0.0) 
Using coffee-script-source (1.6.3) 
Using execjs (2.0.2) 
Using coffee-script (2.2.0) 
Using thor (0.18.1) 
Using railties (4.0.0) 
Using coffee-rails (4.0.0) 
Using hike (1.2.3) 
Using jbuilder (1.5.1) 
Using jquery-rails (3.0.4) 
Using json (1.8.0) 
Using mysql2 (0.3.13) 
Using bundler (1.3.5) 
Using tilt (1.4.1) 
Using sprockets (2.10.0) 
Using sprockets-rails (2.0.0) 
Using rails (4.0.0) 
Using rdoc (3.12.2) 
Using sass (3.2.12) 
Using sass-rails (4.0.0) 
Using sdoc (0.3.20) 
Using turbolinks (1.3.0) 
Using uglifier (2.2.1) 
Your bundle is complete!
Use `bundle show [gemname]` to see where a bundled gem is installed.

$ sudo gem install mysql2 -v 0.3.11 -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin
Fetching: mysql2-0.3.11.gem (100%)
Building native extensions.  This could take a while...
Successfully installed mysql2-0.3.11
1 gem installed
Installing ri documentation for mysql2-0.3.11...
Installing RDoc documentation for mysql2-0.3.11...

gem 'mysql2', '~> 0.3.11'

$ bundle install
Fetching gem metadata from https://rubygems.org/...........
Fetching gem metadata from https://rubygems.org/..
Resolving dependencies...
Using rake (10.1.0) 
Using i18n (0.6.5) 
Using minitest (4.7.5) 
Using multi_json (1.8.1) 
Using atomic (1.1.14) 
Using thread_safe (0.1.3) 
Using tzinfo (0.3.37) 
Using activesupport (4.0.0) 
Using builder (3.1.4) 
Using erubis (2.7.0) 
Using rack (1.5.2) 
Using rack-test (0.6.2) 
Using actionpack (4.0.0) 
Using mime-types (1.25) 
Using polyglot (0.3.3) 
Using treetop (1.4.15) 
Using mail (2.5.4) 
Using actionmailer (4.0.0) 
Using activemodel (4.0.0) 
Using activerecord-deprecated_finders (1.0.3) 
Using arel (4.0.0) 
Using activerecord (4.0.0) 
Using bundler (1.3.5) 
Using coffee-script-source (1.6.3) 
Using execjs (2.0.2) 
Using coffee-script (2.2.0) 
Using thor (0.18.1) 
Using railties (4.0.0) 
Using coffee-rails (4.0.0) 
Using hike (1.2.3) 
Using jbuilder (1.5.1) 
Using jquery-rails (3.0.4) 
Using json (1.8.0) 
Installing mysql2 (0.3.13) 
Using tilt (1.4.1) 
Using sprockets (2.10.0) 
Using sprockets-rails (2.0.0) 
Using rails (4.0.0) 
Using rdoc (3.12.2) 
Using sass (3.2.12) 
Using sass-rails (4.0.0) 
Using sdoc (0.3.20) 
Using turbolinks (1.3.0) 
Using uglifier (2.2.1) 
Your bundle is complete!
Use `bundle show [gemname]` to see where a bundled gem is installed.

$ gem list | grep mysql2
mysql2 (0.3.13, 0.3.11)

$ ls -al
total 160K
-rw-r--r--  1 mysql mysql  18K Sep 10 15:38 COPYING
-rw-r--r--  1 mysql mysql 2.5K Sep 10 15:38 README
-rw-r--r--  1 mysql mysql  87K Sep 10 15:38 INSTALL-BINARY
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:51 docs/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:51 include/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:51 lib/
drwxr-xr-x 10 mysql mysql 4.0K Oct  1 23:52 mysql-test/
drwxr-xr-x 28 mysql mysql 4.0K Oct  1 23:52 share/
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:52 scripts/
drwxr-xr-x  4 mysql mysql 4.0K Oct  1 23:52 sql-bench/
drwxr-xr-x  4 mysql mysql 4.0K Oct  1 23:52 man/
drwxr-xr-x  3 mysql mysql 4.0K Oct  1 23:52 support-files/
-rw-r--r--  1 mysql mysql  943 Oct  1 23:55 my.cnf
drwxr-xr-x  2 mysql mysql 4.0K Oct  1 23:57 bin/
drwxr-xr-x  6 mysql mysql 4.0K Oct  7 01:04 data/

$ sudo gem uninstall mysql2
$ sudo gem install mysql2 -v 0.3.11 --platform=ruby -- --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-lib=/usr/local/mysql/lib --with-mysql-bin=/usr/local/mysql/bin
$ rm -rf Gemfile.lock
$ bundle install

$ sudo apt-get install nodejs

而且，它会起作用的

$ rails server
=> Booting WEBrick
=> Rails 4.0.0 application starting in development on http://0.0.0.0:3000
=> Run `rails server -h` for more startup options
=> Ctrl-C to shutdown server
[2013-10-07 21:08:06] INFO  WEBrick 1.3.1
[2013-10-07 21:08:06] INFO  ruby 1.9.3 (2013-06-27) [i686-linux]
[2013-10-07 21:08:06] INFO  WEBrick::HTTPServer#start: pid=3676 port=3000

不要忘记启动mysql服务器：

$ sudo service mysql start

====================

更新3 CentOS的NodeJS安装：

$ sudo yum groupinstall 'Development Tools'
$ mkdir nodjs && cd $_
$ wget http://nodejs.org/dist/node-latest.tar.gz
--2013-10-12 16:01:53--  http://nodejs.org/dist/node-latest.tar.gz
Resolving nodejs.org... 165.225.133.150
Connecting to nodejs.org|165.225.133.150|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 13633041 (13M) [application/octet-stream]
Saving to: “node-latest.tar.gz”

100%[============================================================================>] 13,633,041   513K/s   in 36s

2013-10-12 16:02:31 (375 KB/s) - “node-latest.tar.gz” saved [13633041/13633041]
$ tar xzf node-latest.tar.gz
$ cd node-v0.10.20/
$ ./configure
$ make
$ sudo make install

===================

注

这与权限问题无关
如果在Gemfile中更新了任何内容，请在运行捆绑安装之前先删除Gemfile.lock

将此添加到GemFile
gem'mysql2'，'~>0.3.11'
并再次尝试绑定。
将此添加到GemFile
gem'mysql2'，'~>0.3.11'
并再次尝试绑定。
我的系统：-Windows 7 64位，MySQL 5.6，Ruby 1.9.3，Rails 4.0.4 执行以下步骤在rails中安装mysql2-

从下载mysql-connector-c-6.1.3-win32.zip

升级到“C:\mysql连接器”

gem安装mysql2--platform=ruby----with mysql dir=“C:\mysql connector”'

将'libmysql.dll'从'C:\mysql connector\lib'复制到'C:\Ruby193\bin'目录

在Genfile中添加gem“mysql2”

删除“Genfile.lock”

捆绑安装

rails服务器
享受
我的系统：-Windows 7 64位、MySQL 5.6、Ruby 1.9.3、Rails 4.0.4 执行以下步骤在rails中安装mysql2-

从下载mysql-connector-c-6.1.3-win32.zip

升级到“C:\mysql连接器”

gem安装mysql2--platform=ruby----with mysql dir=“C:\mysql connector”'

将'libmysql.dll'从'C:\mysql connector\lib'复制到'C:\Ruby193\bin'目录

在Genfile中添加gem“mysql2”

删除“Genfile.lock”

捆绑安装

rails服务器

享受
我在MySQL更新后遇到了这个问题。最后，修复它所需的步骤是：

gem uninstall mysql2 apt-get install libmysqlclient-dev bundle install

…此时已安装更新后的mysql2 gem，rails能够顺利启动。
在MySQL更新后，我遇到了这个问题。最后，修复它所需的步骤是：

gem uninstall mysql2 apt-get install libmysqlclient-dev bundle install

…此时已安装更新的mysql2 gem，rails可以毫无问题地启动。
安装
mysql2
as
marslo
，而不是
root
。ruby的lib已安装在/usr/local/lib/ruby/。我无法通过
marslo
安装gems。顺便说一句，mysql的所有者是
mysql
这里关于在没有
sudo
的情况下安装mysql2的错误是：
$gem安装mysql2--with mysql config=/usr/local/mysql/bin/mysql\u config--with mysql lib=/usr/local/mysql/bin获取：mysql2-0.3.13.gem（100%）错误：执行gem时。。。（Gem:：FilePermissionError）您没有写入/usr/local/lib/ruby/gems/1.9.1目录的权限。
Install
mysql2
as
marslo
，而不是
root
。ruby的lib已安装在/usr/local/lib/ruby/。我无法通过
marslo
安装gems。顺便说一句，mysql的所有者是
mysql
这里关于在没有
sudo
的情况下安装mysql2的错误是：
$gem安装mysql2--with mysql config=/usr/local/mysql/bin/mysql\u config--with mysql lib=/usr/local/mysql/bin获取：mysql2-0.3.13.gem（100%）错误：执行gem时。。。（Gem:：FilePermissionError）您没有写入/usr/local/lib/ruby/gems/1.9.1目录的权限。
只是查看了他的gemfile，但他的bundle输出中没有mysql2 Gem解释了为什么：pHi@David，我有mysql2:
使用mysql2（0.3.13）
我已经更新了gemfile，但是mysql2仍然作为0.3.13安装。这是为什么？更改gemfile.lock或者删除
gemfile.lock
并重新安装捆绑包。查看他的gemfile，他在捆绑包输出中没有mysql2 gem解释了原因：pHi@David，我有mysql2:
使用mysql2（0.3.13）
我已经更新了gemfile，但是mysql2仍然作为0.3.13安装。为什么？更改gemfile.lock或删除
gemfile.lock
，然后重新进行捆绑安装