Error installing mysql2

Question

I am trying to install mysql2 on the server. so my first unlucky trail was as following

gem install mysql2

the output

    Building native extensions.  This could take a while...
ERROR:  Error installing mysql2:
    ERROR: Failed to build gem native extension.

/usr/bin/ruby1.8 extconf.rb
checking for rb_thread_blocking_region()... no
checking for rb_wait_for_single_fd()... no
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lm... yes
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lz... yes
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lsocket... no
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lnsl... yes
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lmygcc... no
checking for mysql_query() in -lmysqlclient... no
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers.  Check the mkmf.log file for more
details.  You may need configuration options.

Provided configuration options:
    --with-opt-dir
    --without-opt-dir
    --with-opt-include
    --without-opt-include=${opt-dir}/include
    --with-opt-lib
    --without-opt-lib=${opt-dir}/lib
    --with-make-prog
    --without-make-prog
    --srcdir=.
    --curdir
    --ruby=/usr/bin/ruby1.8
    --with-mysql-config
    --without-mysql-config
    --with-mysql-dir
    --without-mysql-dir
    --with-mysql-include
    --without-mysql-include=${mysql-dir}/include
    --with-mysql-lib
    --without-mysql-lib=${mysql-dir}/lib
    --with-mysqlclientlib
    --without-mysqlclientlib
    --with-mlib
    --without-mlib
    --with-mysqlclientlib
    --without-mysqlclientlib
    --with-zlib
    --without-zlib
    --with-mysqlclientlib
    --without-mysqlclientlib
    --with-socketlib
    --without-socketlib
    --with-mysqlclientlib
    --without-mysqlclientlib
    --with-nsllib
    --without-nsllib
    --with-mysqlclientlib
    --without-mysqlclientlib
    --with-mygcclib
    --without-mygcclib
    --with-mysqlclientlib
    --without-mysqlclientlib


Gem files will remain installed in /home/aaalsubaie/.gems/gems/mysql2-0.3.11 for inspection.
Results logged to /home/aaalsubaie/.gems/gems/mysql2-0.3.11/ext/mysql2/gem_make.out

this is not the end of the story

after running

[ps89405]$ mysql --help | grep Default -A 1
Default options are read from the following files in the given order:
/etc/my.cnf /etc/mysql/my.cnf /usr/etc/my.cnf ~/.my.cnf 

I tried

 gem install mysql2 -- --with-mysql-config=~/.my.cnf --ruby=/usr/bin/ruby1.8

and

gem install mysql2 -- --with-mysql-config=/usr/etc/my.cnf --ruby=/usr/bin/ruby1.8

and

gem install mysql2 -- --with-mysql-config=/etc/my.cnf --ruby=/usr/bin/ruby1.8

no luck the same error.

I dont run rvm

and my gem env is

   RubyGems Environment:
  - RUBYGEMS VERSION: 1.3.7
  - RUBY VERSION: 1.8.7 (2010-08-16 patchlevel 302) [x86_64-linux]
  - INSTALLATION DIRECTORY: /home/aaalsubaie/.gems/
  - RUBY EXECUTABLE: /usr/bin/ruby1.8
  - EXECUTABLE DIRECTORY: /home/aaalsubaie/.gems/bin
  - RUBYGEMS PLATFORMS:
    - ruby
    - x86_64-linux
  - GEM PATHS:
     - /home/aaalsubaie/.gems/
     - /usr/lib/ruby/gems/1.8
  - GEM CONFIGURATION:
     - :update_sources => true
     - :verbose => true
     - :benchmark => false
     - :backtrace => false
     - :bulk_threshold => 1000
  - REMOTE SOURCES:
     - http://rubygems.org/

this is my second days on row trying to deploy my first rails app with no luck I though it will be much easier.

update:

now the command is working and installing mysql2 gem thanks to Yanhao

gem install mysql2 -- --with-mysql-config=/usr/bin/mysql_config

I have new issue now with mysql2 gem when i run

bundle exec rails console

I got

/home/aaalsubaie/ajhezaty.com/releases/20120411095320/vendor/bundle/ruby/1.8/gems/mysql2-0.3.11/lib/mysql2.rb:9:in `require': no such file to load -- mysql2/mysql2 (LoadError)
from /home/aaalsubaie/ajhezaty.com/releases/20120411095320/vendor/bundle/ruby/1.8/gems/mysql2-0.3.11/lib/mysql2.rb:9
from /usr/lib/ruby/gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:64:in `require'
from /usr/lib/ruby/gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:64:in `require'
from /usr/lib/ruby/gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:62:in `each'
from /usr/lib/ruby/gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:62:in `require'
from /usr/lib/ruby/gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:51:in `each'
from /usr/lib/ruby/gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:51:in `require'
from /usr/lib/ruby/gems/1.8/gems/bundler-1.0.7/lib/bundler.rb:112:in `require'
from /home/aaalsubaie/ajhezaty.com/releases/20120411095320/config/application.rb:7
from /home/aaalsubaie/ajhezaty.com/releases/20120411095320/vendor/bundle/ruby/1.8/gems/railties-3.2.1/lib/rails/commands.rb:39:in `require'
from /home/aaalsubaie/ajhezaty.com/releases/20120411095320/vendor/bundle/ruby/1.8/gems/railties-3.2.1/lib/rails/commands.rb:39
from script/rails:6:in `require'
from script/rails:6

Answer 1

This may not be directly relevant to you, but I faced the exact same problem, and I think my answer may help others with this issue:

sudo apt-get install libmysql-ruby
sudo apt-get install libmysqlclient-dev
sudo gem install mysql2

That worked for me.

Answer 2

If you are on a Mac, install MySQL with Homebrew brew install mysql and that should let you install the gem after.