So it looks like Sun is restricting what features go in to the open source version of MySQL. The Slashdot thread is full of anti-sun FUD, but the blog post linked in the Slashdot thread is true. Sun is providing features to the “enterprise” customers that are unavailable in the GPL version.
I like to refer to such restrictions as semi-open source. The problem with such arrangements is that its just as restrictive as proprietary software. Oh you want online backups for your database? You need the proprietary “enterprise” version.
With such arrangements, the openness of the software is essentially a farce. I’ve seen this the past with “open source” groupware. Zimbra may utilize open source components, buts its no better than Exchange when it comes to being open. Oh you want connect Outlook with Zimbra? You need the “enterprise” edition with its per user per year licensing.
Semi-open source may have packaging that looks open, but when you open the box, its really just proprietary software disguised as open source. In the case of MySQL, organizations are better off using Postgres anyway. Why use an inferior product that isn’t really open?