Please note that since release 4.0 is now production level, only critical fixes are done in the 3.23 release series. You are recommended to upgrade when possible, to take advantage of all speed and feature improvements in 4.0. See 項2.5.2. 「バージョン 3.23 から 4.0 へのアップグレード」.

The 3.23 release has several major features that are not present in previous versions. We have added three new table types:

Note that only MyISAM is available in the standard binary distribution.

The 3.23 release also includes support for database replication between a master and many slaves, full-text indexing, and much more.

All new features are being developed in the 4.x version. Only bug fixes and minor enhancements to existing features will be added to 3.23.

The replication code and BerkeleyDB code is still not as tested and as the rest of the code, so we will probably need to do a couple of future releases of 3.23 with small fixes for this part of the code. As long as you don't use these features, you should be quite safe with MySQL 3.23!

Note that the above doesn't mean that replication or Berkeley DB don't work. We have done a lot of testing of all code, including replication and BDB without finding any problems. It only means that not as many users use this code as the rest of the code and because of this we are not yet 100% confident in this code.