Scans your WordPress system and identifies and deletes unused database tables from uninstalled plugins. This plugin also allows you to optimize DB Tab
WPDBSpringClean identifies only those database tables which are considered not part of any of your installed plugins (either ACTIVE or INACTIVE). When WPDBSpringClean has finished its query it will list all of the tables it believes are not being used and it will give you the option of deleting some or all of these tables.
(As a matter of prudence it is recommended that you take a DB backup if you are unsure about deleting particular tables)