Cloud and web database Drizzle reaches general availability
The first GA (General Availability) release of Drizzle, the lightweight DBMS for cloud and web applications, has been released as Drizzle7 GA. Drizzle is described by its developers as an "open source microkernel DBMS for high performance scale-out applications" and began development in July 2008 as a fork by Sun employees aimed at getting MySQL back to its roots, powering web applications. Drizzle7's beta was released in September 2010.
To create Drizzle, the developers removed non-essential code from MySQL and then re-factored the code that remained, while simultaneously migrating that code to C++. Drizzle has been developed around the concept of microkernels and is focussed on having a modular architecture. Much of the functionality is outsourced to modules, allowing them to be more easily replaced by improved or specialised versions.
Drizzle can be used as a replacement for MySQL. The drizzledump tool enables the migration of data between MySQL and Drizzle. When connected to a Drizzle server, drizzledump behaves as a normal dump command, but when connected to a MySQL server, it converts all the structures and data into a Drizzle compatible format which can be sent directly to a Drizzle server. Drizzle is also capable of understanding MySQL's network protocol; this should allow MySQL applications to run with it with only minor changes. A detailed explanation of the differences between MySQL and Drizzle is available.
Drizzle uses InnoDB as its transactional storage engine, which is now also the default in the most recent versions of MySQL. Drizzle also supports PBXT as a storage engine and plug-ins are available for the Embedded InnoDB engine and HailDB – the latter may become the default storage engine in the future. Drizzle can support various scripting languages for writing stored procedures.
The Drizzle source code is available to download. Drizzle can be built on Mac OS X, Linux and Solaris x86 and SPARC. Ubuntu users can install from a PPA repository (Drizzle is already in the 11.04 Natty Narwhal repositories) and instructions for installing binaries on Red Hat and Fedora are available. Drizzle is licensed under the GPLv2 with newly contributed code retaining whatever open source licence with which it was contributed. An FAQ on the project's Wiki explains more of the design choices and development process of Drizzle.