I spend far too long search for this each time I have to do it

1. cd ~
2. Download the PHP source for the version your using (php -i to get version)
3. tar -xzf php-source.tar.gz
4. cd php-source/ext/mysql
5. sudo phpize ./
6. sudo ./configure –with-zlib-dir=/usr/include –with-mysql-sock=/var/lib/mysql/mysql.sock –with-libdir=lib64 –with-mysql=/usr/bin
7. make
8. make install