Uninstall Methods

Your plugin may need to do some clean-up when it is uninstalled from a site.

A plugin is considered uninstalled if a user has deactivated the plugin, and then clicks the delete link within the WordPress Admin.

When your plugin is uninstalled, you’ll want to clear out any plugin options and/or settings specific to the plugin, and/or other database entities such as tables.

Less experienced developers sometimes make the mistake of using the deactivation hook for this purpose.

This table illustrates the differences between deactivation and uninstall.

Scenario	Deactivation Hook	Uninstall Hook
Flush Cache/Temp	Yes	No
Flush Permalinks	Yes	No
Remove Options from {$ wpdb ->prefix}_options	No	Yes
Remove Tables from wpdb	No	Yes

Method 1: register_uninstall_hook

To set up an uninstall hook, use the register_uninstall_hook() function:

 register_uninstall_hook( __FILE__, 'pluginprefix_function_to_run' );

Method 2: uninstall.php

To use this method you need to create an uninstall.php file inside the root folder of your plugin. This magic file is run automatically when the users deletes the plugin.

For example: /plugin-name/uninstall.php

Here is an example deleting option entries and dropping a database table:

 // if uninstall.php is not called by WordPress, die if ( !  defined( 'WP_UNINSTALL_PLUGIN' ) ) { die; } $option_name = 'wporg_option'; delete_option( $option_name ); // for site options in Multisite delete_site_option( $option_name ); // drop a custom database table global $wpdb; $wpdb->query( "DROP TABLE IF EXISTS {$wpdb->prefix}mytable" );