When Sun acquired MySQL and announced that it would invest the resources necessary to position the open source database for mission-critical deployments, I think everyone assumed that the database would eventually become bigger and heavier.

Few would have predicted that we would also see a project that would make the database smaller and lighter, but that is exactly what Drizzle, a new project from Sun’s MySQL director of architecture Brian Aker, is all about.

Drizzle is taking a back-to-the-drawing-board approach to refactoring MySQL by ripping out much of the additional enterprise functionality that has gone into it since version 4.1 and focusing on the demands of a core set of applications.

As Brian explains : “Stored Procedures, Views, Triggers, Query Cache, and Prepared Statements are gone for now. The field types have been simplified and there is an open debate about the SHOW commands (I am falling into the camp that think they may just belong in the client application but not in the server). Will any of this go back in? It is hard to say. The goal right now is to target a certain class of applications/developers and see if this is useful. As an example:

1) Web based apps.
2) Cloud components.
3) Databases without business logic (aka stored procedures).
4) Multi-Core architecture.”

The project also has a more community-centric development philosophy, although it is not clear from the FAQ what the copyright implications are for would-be contributors.

Brian announced the project with the caveat that it is “not looking to be 100% compatible with MySQL” and “certainly not a replacement for MySQL” which is important to consider, but the project clearly has the blessing of MySQL CTO Monty Widenius who has stated that “Drizzle solves many of the problems that MySQL’s development has had for years.”

Among the benefits noted by Monty are:

* “It opens up MySQL development for the community; You no longer have to wait years to get your patches and reasonable extensions into the server.

* Critical bugs that have existed for years can finally get fixed as the development is no longer constrained by unrealistic release schedules that put artificial constraints on things that can be fixed.

* Drizzle will put some MySQL server differentiation on a true test; A bit like Fedora does to Red Hat.

* Drizzle has created new excitement in the MySQL developer community; A lot of people seem to be very enthusiastic to work on it in a true community-oriented manner.

* Developers working on Drizzle is doing drastic refactoring of the server, something that MySQL planned to do years ago but never happened.

* Development decisions is again driven by people that are using the server daily; This will ensure that Drizzle will be faster and more stable than what can be done with current MySQL development model

* Drizzle will target the MySQL core users, the web users, whose requirements have been ignored for years while the core MySQL developers have added features that they don’t need.

* In addition Drizzle will include the latest InnoDB code; You don’t have to wait for MySQL 6.0 or go to the trouble of annually downloadoing and installing the InnoDB plugin from Oracle just to get access to the latest and fastest InnoDB version.”

It is interesting to see Monty mention Drizzle as a potential Fedora-like project, especially given his link to ProvenScaling’s publication of MySQL sources and binaries and a blog post from Peter Zaitsev wondering whether it makes MySQL Community redundant.

It would be wrong to claim that as an official endorsement, but MySQL is clearly not trying to discourage community-led projects while it has also moved its sources to Bazaar and Launchpad to (as Kaj Arno puts it) “expand our external contributor base”.

All in all it is fascinating to see that MySQL, which many would consider one of the more mature open source projects, continues to evolve and experiment, especially now it has more freedom to do so as part of Sun. As Monty says:

“Drizzle is one of the good things that have been made possible by Sun acquiring MySQL. Brian has been working on Drizzle with the blessing and encouragement from Sun’s upper management. We are finding Sun to be open and encouraging of innovation, this has been a good aspect of the acquisition.”