MySQL may be the most popular database in the world. Or it may not be, it depends on who you listen to. The fact that it is even mentioned as this potential is enough to show it's popularity and use. It has a long history in the open source community and it is now owned by Oracle. This association with Oracle has raised questions as to the future of this open source project. Some users have dropped it and many are reluctant to use it.
What we like about MySQL:
- Oracle has put resources into it. Development continues and major enhancements are being made.
- The product is solid.
- Most colleges use it for teaching.
- Public support is widely available through forums, books, and tutorial websites.
- Many open source projects use it so it has the potential to be integrated with other open source projects.
What we don't like about MySQL:
- Owned by Oracle and not community driven.
- Confusing and unclear licensing.
- Uncertain future is as unclear as its licensing. Many major users of MySQL are moving on.
The big question surrounding MySQL is it’s association with Oracle and it’s licensing. No one seems to understand it thus there is growing reluctance to use it. Another database, MariaDB, is a “drop in” replacement for MySQL and was developed as a fork of the MySQL project by one of the original developers of MySQL. Here's a nice review: http://www.smartfile.com/blog/the-pros-and-cons-of-mysql/