MySQL development is ongoing, and MySQL AB releases new versions frequently. New versions add new features and correct problems found in older versions. Nevertheless, you should not upgrade to a newer version of MySQL without checking the implications and possible difficulties of doing so. Check the MySQL Reference Manual before performing any upgrade:
Despite those cautionary remarks, upgrading MySQL usually is straightforward and can be done using the following procedure:
If you install a new version of MySQL on top of an existing one, you might not need to do much reconfiguring. This is common for Windows installations, RPM installations, and installations from source because those types of distributions each tend to use the same installation directory location regardless of MySQL version. However, if you upgrade MySQL using a tar file, the new distribution likely will create a new version-specific base installation directory that differs from your existing installation directory. In this case, some reconfiguration might be necessary. If you have a symbolic link set up that points to the old installation directory, you can delete the link and re-create it to point to the new installation directory. Subsequent references to the new symbolic link will access the new installation. Upgrading MySQL sometimes gives you access to new security features. See Chapter 36, "Upgrade-Related Security Issues," for information about taking advantage of them. |