Command line:
gem install mysql2


rake db:schema:dump //generate db/schema.rb
rake db:create //create database
rake db:schema:load // load schema
rake db:migrate //migrate
rake db:seed //seed


config/database.yml should

#==============================
development:
   adapter: mysql2
   database: rails_blog
   username: root
   password: talha012
   host: localhost
   socket: /tmp/mysql.sock

test:
   adapter: mysql2
   database: rails_blog
   username: root
   password: talha012
   host: localhost
   socket: /tmp/mysql.sock

production:
   adapter: mysql2
   database: rails_blog
   username: root
   password: talha012
   host: localhost
   socket: /tmp/mysql.sock
  # =================================