Most big companies will not use MySql for their software for it cant handle very large amount of requests and data. in most cases they will use MS-SQL (Microsoft) or a Oracle based data base.

In the following tutorial you will learn how to install Ms-SQL for PHP, and how to use it:
http://docs.moodle.org/24/en/Installing_MSSQL_for_PHP

I recommand trying this first hand, installing a database can be tricky.

Good luck!