Apart from writing Good content for your blog, it is also very important do some housekeeping tasks, specially when you are managing the hosting environment yourself. As traffic grows it also comes with spam and other unwanted things like fragmentation of database which may slow down the performance. Post revisions may pile up taking valuable resources in the database.
All these housekeeping tasks can be done easily with a single button click. WP-Optimize is a free plugin which can be used to optimize you database without going into technical details of queries and other kind of optimizations.
Based on your selection it can remove post revisions, comments marked as spam, unapproved comments and Drafts. After cleaning it also displays a summary something like below.
And at last optimization done at the tables, showing number of KB space recovered.
For more details visit WP-Optimize plugin page at Wordpress.org