I've been getting errors that show up from this plugin.
[13-Oct-2013 04:01:48] PHP Notice: Undefined index: action in /home/draftb5/public_html/wp-content/plugins/wp-database-optimizer/wp_database_optimizer.php on line 14
I tried editing your code to add 'isset()' around the $_GET['action'] if statement, but that didn't work. I was getting so many of these notices that my error log was REALLY getting large, so I have to keep the plugin deactivated.
Other than that, the plugin seem to work great. Hopefully you can make a fix. Thanks!