<?php
/*
  howto uninstall the pluggin
  https://developer.wordpress.org/plugins/plugin-basics/uninstall-methods/
*/

// if uninstall.php is not called by WordPress, die
if (!defined('WP_UNINSTALL_PLUGIN')) {
    die;
}

$option_name = 'arcHIVE_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}arcHIVEplugin");

?>