Note: Marten Mickos responds to this editorial below.

Sun Microsystems' purchase of the MySQL database system worried many open source programmers. MySQL is the back-end for a huge number of online applications, including Facebook and Slashdot. Sun made promises when they acquired MySQL. The two major promises were that they would continue to support MySQL in all of the environments it currently runs in and that it would remain open source.

The first promise, to maintain support on all platforms, is extremely important to the Linux community. MySQL is the essential back-end component to the LAMP (Linux, Apache, MySQL, PHP/Perl/Python) stack that drives the $21 billion dollar Linux server industry. But Information Week reported that Sun is already focusing on a SAMP stack. The S in SAMP stands for Solaris, Sun's Unix-like operating system. Sun's emphasis of Solaris over Linux is troublesome for many developers.

Even more troublesome, however, is Sun's breaking the promise to keep MySQL as open source. They recently announced that several new features in MySQL will be available to paying customers only, and that these features will be closed source — this in direct contrast to their earlier claims. What it does, in effect, is create a model where paying customers will be using code untested by the community at large. This is the exact opposite of the "many eyeballs" method of open source bug testing.

I understand Sun's need to recoup the one billion dollars they spent in acquiring MySQL, but they are moving in a dangerous direction. By emphasizing Solaris over Linux, and closing off new features to paying customers only, they are essentially saying that Linux doesn't matter. This is the wrong view for Sun to take if they want to maintain a strong user base. Open source proponents will quickly make the leap to other database back-ends, even if it demands major rewrites to their code, rather than work with a company that breaks its promises to the community. At the very least, Sun is courting a fork of the MySQL project. At worst, they are inviting the mass exodus of programmers from MySQL databases.

There are other options, of course, including PostgreSQL and Firebird, but they don't have the significant market share that MySQL enjoys. In many ways, MySQL is the database that makes the Internet work. Sun's lie will generate shockwaves, and it is impossible to predict how it will change the landscape, but there's no doubt that it will change it. I can only hope that Sun comes to its senses and changes its mind before it's too late to make peace with the open source community.