This is the Reference Manual for the MySQL Database System, version 5.1, up to release 5.1.5-alpha. It is not intended for use with older versions of the MySQL software due to the many functional and other differences between MySQL 5.1 and previous versions. If you are using an earlier release of the MySQL software, please refer to the MySQL 5.0 Reference Manual, which provides coverage of MySQL 5.0, or to the MySQL 4.1 Reference Manual, which covers MySQL 4.1 and all earlier versions of MySQL. Differences between minor versions of MySQL 5.1 are noted in the present text with reference to release numbers (5.1.x).