If your WordPress blog has been around for awhile, chances are there is some clutter in your MySQL database. For these situations, Joost De Valk of Yoast.com has an easy to use WordPress plugin called Optimize Database.
This free WordPress plugin simply needs activated, then whenever you click Optimize Now, the plugin runs an
optimize table command on your WordPress tables, effectively defragmenting it. This is very useful for tables that are frequently updated. If you’d like to learn more about why this WordPress plugin might be necessary, you can read more information on this post.
Great plugin Joost!