Hat tip to Colin Charles at MariaDB for this: http://blog.mariadb.org/mysql-man-pages-silently-relicensed-away-from-gpl
Why is this important? The MySQL documentation already has a restrictive license. This means that it’s illegal to redistribute the MySQL documentation. As a counterexample, the PHP documentation is licensed under a Creative Commons Attribution license, and there are many mirrors of it. If one mirror goes down, it is easy to find another mirror to look up whatever you want to look up. I’ve been stuck without MySQL documentation before, because their servers were down.
The man pages are an even bigger deal in a way, even though they’re probably used less often. The relevant difference here is that the man pages are distributed with MySQL. Percona, MariaDB, and others may now need to write their own man pages, using previous GPL versions as the basis for them. My reading of the license suggests that this would NOT affect distributions such as Red Hat, Fedora, or Ubuntu, since they probably republish it as is, without reference to any additional features or options.
Here is the section of the new license that seems relevant to me:
This documentation is NOT distributed under a GPL license. Use of this documentation is subject to the following terms:You may create a printed copy of this documentation solely for your own personal use. Conversion to other formats is allowed as long as the actual content is not altered or edited in any way. You shall not publish or distribute this documentation in any form or on any media, except if you distribute the documentation in a manner similar to how Oracle disseminates it (that is, electronically for download on a Web site with the software) or on a CD-ROM or similar medium, provided however that the documentation is disseminated together with the software on the same medium. Any other use, such as any dissemination of printed copies or use of this documentation, in whole or in part, in another publication, requires the prior written consent from an authorized representative of Oracle. Oracle and/or its affiliates reserve any and all rights to this documentation not expressly granted above.
According to Oracle, this was just a bug. Since the above notice is fairly specific about (1) NOT being GPL, and (2) applying to the documentation, the suspicious part of me wonders if the “bug” was just that there was more uproar about it than they intended. I’m going to take them at their word, though, and assume that this notice was meant for the Enterprise (non-GPL) version of MySQL.