MySQL is the most widely-used open-source database in the world. Many popular open-source applications, from WordPress to SugarCRM to Joomla!, use it. And popular websites like Facebook and Twitter rely on it as well.

The popular database system is offered by MySQL AB, which was purchased by Sun Microsystems in 2008. Sun Microsystems, of course, was just purchased for $7.4bn by database and enterprise software giant Oracle.

But lest anyone worry about the future of MySQL under Oracle’s umbrella, yesterday saw the preview release of the next version of MySQL, 5.4. And boy does it look hot.

Amongst the highlights:

  • Subquery optimizations that improve the importance of certain queries by up 90%.
  • Improved stored procedures and prepared statements.
  • 16 processor support for x86 servers and 64 processor support for Sun SPARC-based servers.

betanews delves deeper and provides some interesting perspectives about MySQL and the evolution of its support for the InnoDB database engine, and Allan Packer has some interesting scalability tests of his own.

If you’re not a MySQL geek, here’s what you need to know: MySQL is getting more robust and it’s getting faster.

A few years ago, I was involved with a large development project and we opted to go with PostgreSQL, another open-source MySQL alternative/competitor, because it had more of the ‘enterprise‘-like features we desired. If I had to make the same decision today, it would be hard for me to come up with a rationale for not choosing MySQL instead. From the looks of it, things are only getting better with 5.4 and the level of continued development is impressive.

That’s good news if you’re working with or building applications based on MySQL. And it could be good news for Oracle, although there’s plenty of debate and there is a risk that Oracle’s purchase of Sun/MySQL will drive key employees away. Even though, on the surface, MySQL could be perceived as a (minor) threat to Oracle Database, the reality is that Oracle has always been an enterprise DB while MySQL’s niche is web applications.

Since most MySQL users can’t afford Oracle anyway, I think it’s unlikely that Oracle is going to fuss around too much with MySQL; Oracle executives are promising as much.

In the meantime, while MySQL 5.4 won’t hit general release until later in the year, as the pharmaceutical ads say, talk to your developer/database administrator to see if a MySQL 5.4 upgrade may be right for you.