Joomla - delete tables from your database according to a certain prefix

A recent post on the Joomla French forum was asking how to delete tables present in the Joomla database; the ones using a given prefix like old_ or something like that.

Indeed, from time to time, it can be useful to take a look at the list of tables in your database and perhaps, you'll find tables prefixed with f.i. old_ or an old tool you've used years ago (using the correct prefix but with a component you've removed since, like joomla_oldcomp).

Years ago, I wrote such a PHP utility; let's see how to use it.

What the utility looks like​

Type a prefix in the text field and the utility immediately lists every table of your Joomla database matching it. Tick the ones you want gone, click Kill selected tables, and they're dropped. The Remove this script button on the right deletes the utility from your server once you're done.

That's the whole tool: one screen, one text field, no configuration file.

How to use it​

1. Click on the link https://github.com/cavo789/joomla_free/blob/master/src/kill_db_tables/kill_db_tables.php to get a copy of my PHP utility,
2. Copy/download the script and using your FTP client (WinSCP f.i.), upload the script to your Joomla site, in the same directory as your configuration.php file. Name the script like, f.i., delete_tables.php,
3. Open your internet browser and go to the URL of your website and access delete_tables.php, so f.i. https://yoursite.com/delete_tables.php
4. In the text field, just start to type your prefix and you'll get the list of tables using that prefix. Once you're sure, just click on the Kill selected tables button.
5. Finally, be sure to click on the Remove this script button since the script shouldn't stay there.

Conclusion​

A leftover old_ or joomla_oldcomp prefix is the kind of clutter you notice once a year and never take the time to clean, because doing it by hand in phpMyAdmin means ticking thirty checkboxes without being sure. This script does the selection for you, in one screen, and then removes itself.

Before dropping anything, take the time to look at what those tables contain: Joomla - Run a SQL statement outside Joomla and display a nice HTML table is the read-only companion of this utility.