I had to use PHPMyadmin a few days ago to delete old tables in my WordPress Database. They were created by a plugin that I tried but decided not to use.
Normally when you uninstall a plugin the developer deletes the tables in your database that they create. In this case this author didn’t. It was easy to identify the author by using another plugin called WP-Optimize. That shows you the database tables easily inside that tool, and then sometimes it will identify the plugin that created it.
If the table isn’t identified you can do a web search on the name of the table, and it normally comes right up. There are many tables that are part of a default WordPress installation so you begin to learn those by doing this.
There is a risk by deleting tables. You can screw up how your WordPress works. I did that in the past when I deleted a table that I thought wasn’t important. I was able to fix the problem by restoring the data using my backup plugin at the time. Right now my backup plugin is BlogVault which I haven’t had to use yet. Before you do anything suggested in this article, make sure you have a backup of your site just in case.
If you can mess up your site by deleting tables, why would I suggest you do it? For several reasons. 1. Dead space in your database counts against your storage limit with your hosting provider. 2. Junk in your database slows down your site performance. 3. Deleting unused tables is just another part of maintaining a database. If you are never going to use them, there is no reason to have them.
I mentioned WP-Optimize earlier. I run this program manually after I delete WordPress database information like posts or photos. Since I do this, the site responds as quickly as possible. The smaller your WordPress database, the faster it can respond to requests for information.
This is easier to do than you think and if this scares you, you can identify the tables and ask your hosting provider to delete them. Be sure your backup is ready. Good luck.