What you should do to solve this problem, is to edit your php.ini file.
run where is php.ini
I found mine at:
/etc/php/php.ini (although I don't know what OS you are running simple find yours)
Look for these two files:
extension=pdo_mysql.so
extension=mysqli.so
and uncomment them. Voila, that would get the job done anytime.
Further reading: https://wiki.archlinux.org/index.php/PHP
