Lenz Grimmer's blog

The modular concept of MySQL that separates the storage engines from the SQL parser and optimizer has recently caused a number of new, independently developed storage engines to surface. Here's an incomplete selection of projects around this concept:

• DDE - Distributed Data Engine, a research project of the Technical University of Dresden
• mdbtools - a storage engine that allows readonly access to Microsoft Access .mdb database files
• PBXT - a new, transactional storage engine by Paul McCullagh
• ritmarkFS - a storage engine that represents the content of a directory as a table
• solidDB - another transactional storage engine with many features, developed by Solid.

Also check the MySQL plugins category on the MySQL Forge for more of these and please add more to the Forge Project directory, if you are aware of other interesting MySQL plugins!

Currently, the integration of these engines into the server is still a bit tricky, as it requires patching and recompiling of the server sources. Hopefully all this won't be required in the near future, when our truly pluggable storage engine API in MySQL 5.1 has matured enough. It's very exciting to watch these projects to evolve.

And did you know that not only storage engines will be pluggable? MySQL 5.1 and up supports a plugin API that will allow the loading and unloading of other server components at runtime, without having to restart the server. This is intended as a more flexible replacement of the old UDF (user defined functions) interface. It will provide more modularity in the future - currently it already provides an API to implement different full-text parser plugins. This can be useful if you need to index context in other formats, e.g. PDF files or word documents. I am curious to see what other new plugins people will come up with in the future.

If you happen to use MySQL and live around Hamburg, Germany, here's your chance to meet with other MySQL users, developers and DBAs: I am happy to announce the second Hamburg MySQL Usergroup Meeting, which will take place on Monday, 3rd of July, 19:00. The location will be the same one as last time, the chinese restaurant Ni Hao in Hamburg-Wandsbek.  The food there is quite excellent and they will provide us with a separate room and video projector again. I'll try to arrange a presentation about MySQL and there will be plenty of time for chatting and discussing. If you'd like to join us, please RSVP via our event page on meetup.com and join the mailing list for further details! Looking forward to meeting you! Some pictures of our last meeting are available in my gallery.

While I was at the FOSDEM 2006 in Brussels, I got approached by the folks from Source21.nl about performing an interview about MySQL with them. But as David Axmark (who is one of the co-founders of MySQL) was around as well, I quickly directed them to talk with him instead. The vidcast (length is ~10 minutes, the WMV is ~30MB) is now available online in various formats (OGG, MP4 and WMV) from their web site. Have fun.

The MySQL code base is quite portable - we do build it on a wide variety of compilers, operating systems and architectures, sometimes just to test if it actually builds and passes the test suite. In fact, some bugs only surface under certain environments, so maintaining this diversity helps us to catch problems quickly. But of course there are still many platforms that are not directly supported or no longer maintained. For example, we removed support for OS/2 from our code base some time ago.

Just recently, somebody from Stratus posted patches to make MySQL build on the Stratus OpenVOS environment to our internals mailing list (which by they way is a great forum to discuss patches and hacking on MySQL with the developers directly - but not to ask support requests!). So if you are interested in getting MySQL up and running on VOS, you might want to get in touch with Paul Green from Stratus about this!

Paul McCullagh works on a new pluggable transactional Storage Engine for MySQL, called PrimeBase XT. I met him for an interview a few days ago - you can now read it on the MySQL Developer Zone. Enjoy and have a nice weekend!