public static function wpmu_drop_tables($tables)
{
global $wpdb;
$tables[] = $wpdb->prefix . 'woocommerce_sessions';
$tables[] = $wpdb->prefix . 'woocommerce_api_keys';
$tables[] = $wpdb->prefix . 'woocommerce_attribute_taxonomies';
$tables[] = $wpdb->prefix . 'woocommerce_downloadable_product_permissions';
$tables[] = $wpdb->prefix . 'woocommerce_termmeta';
$tables[] = $wpdb->prefix . 'woocommerce_tax_rates';
$tables[] = $wpdb->prefix . 'woocommerce_tax_rate_locations';
$tables[] = $wpdb->prefix . 'woocommerce_order_items';
$tables[] = $wpdb->prefix . 'woocommerce_order_itemmeta';
$tables[] = $wpdb->prefix . 'woocommerce_payment_tokens';
$tables[] = $wpdb->prefix . 'woocommerce_shipping_zones';
$tables[] = $wpdb->prefix . 'woocommerce_shipping_zone_locations';
$tables[] = $wpdb->prefix . 'woocommerce_shipping_zone_methods';
return $tables;
}