This section describes the general MySQL development history, provides an overview about features that have been implemented in previous series and that are new in MySQL 5.5, the release series covered in this manual. The maturity level this release series is general availability. Information about maturity levels can be found in Section 2.1.2, “Which MySQL Version and Distribution to Install”.
Before upgrading from one release series to the next, please see the notes in Section 2.11.1, “Upgrading MySQL”.
The most requested features and the versions in which they were implemented are summarized in the following table.
|R-trees||4.1 (for the |
|Stored procedures and functions||5.0|
|Triggers||5.0 and 5.1|
|Pluggable storage engine API||5.1|
|Server log tables||5.1|
|Scalability and performance improvements||5.1 (with InnoDB Plugin)|
|InnoDB as default storage engine||5.5|
|SIGNAL/RESIGNAL support in stored routines||5.5|
|Supplementary Unicode characters||5.5|