Rails, install gem mysql2 error

username@Macbook-Pro~/Documents/workspace/RoR/rails_projects/twitter/config$ gem in
stall mysql2 > ~/Desktop/outputfile
ERROR:  Error installing mysql2:
    ERROR: Failed to build gem native extension.

        /Users/username/.rvm/rubies/ruby-1.8.7-p352/bin/ruby extconf.rb
checking for rb_thread_blocking_region()... 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... no
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
neces开发者_开发技巧sary 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=/Users/username/.rvm/rubies/ruby-1.8.7-p352/bin/ruby
    --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 /Users/username/.rvm/gems/ruby-1.8.7-p352/gems/mysql2-0.3.6 for inspection.
Results logged to /Users/username/.rvm/gems/ruby-1.8.7-p352/gems/mysql2-0.3.6/ext/mysql2/gem_make.out

What is wrong with it? How should I fix this? Thank you so much

EDIT:

I found another SO link for installing MySQL. Try following this first before trying homebrew.
Unable to install MySQL on Mac OS X

Homebrew:

Using homebrew is an alternative solution to installing MySQL.
Actually I use homebrew for almost everything else.

This is the installation link with the docs.
https://github.com/mxcl/homebrew/wiki/installation

The basic commands / readme.
Link

Once it is installed, you can just

brew install mysql

Here are some google search results (search is brew install mysql) that could guide you.
The SO link is if you are having root password issues.
http://solutions.treypiepmeier.com/2010/02/28/installing-mysql-on-snow-leopard-using-homebrew/
brew install mysql on macOS

Before the installation of mysql gem install following. this is for ubuntu ..

sudo apt-get install mysql-server mysql-client
sudo apt-get install libmysql-ruby libmysqlclient-dev