Delete the orphaned product variations that exist on your WooCommerce site

This snippet will delete orphaned WooCommerce product variations from the database. These are product variations that the main product was deleted.

<?php

// Please make a backup of your database before running this snippet
// This snippet should only be ran in "Manual" mode.

global $wpdb;

$deleted_variations = $wpdb->get_rows("DELETE o FROM {$wpdb->posts} o LEFT OUTER JOIN {$wpdb->posts} r ON o.post_parent = r.ID WHERE r.id IS null AND o.post_type = 'product_variation'");

echo "There are $deleted_variations variations on your site.";