ERROR: Failed to build gem native extension (mysql2 on rails 3.2.3)

just copied this in the console

sudo apt-get install mysql-client libmysqlclient-dev

and worked!!

mysql ruby-on-rails mysql2

I used Homebrew for Mac to install mysql:

brew install mysql

Then I used a gem command to install the mysql2 gem:

sudo gem install mysql2

mysql ruby-on-rails mysql2

This is mostly due to lack of mysql headers, Try to install mysql developer (mysql-devel) packages

Normally this error comes when 'libmysqlclient-dev' package is missing

CodeHunter