There is one metric where MySQL far surpasses Oracle's RDBMS: Developer mindshare in open-source projects. If I'm starting out learning PHP, you can bet that I'

There is one metric where MySQL far surpasses Oracle's RDBMS: Developer mindshare in open-source projects. If I'm starting out learning PHP, you can bet that I'm going to be learning Maria/MySQL and not Oracle. This has the side effect that not many open source projects support Oracle. (Wordpress? Drupal? PhpBB?) In fact, I'm not aware of any PHP projects that do support Oracle's RDBMS. There is another metric where MySQL shines: Ease of installation. On any server I come across, I can install and startup a new MySQL/MariaDB instance by just asking for `apt-get install mysql`, or whichever package manager my distribution is using. You can't install Oracle in a single command like that. I'm not aware of any distributions that carry Oracle in their repositories, making it a pain to update and manage.