Порядок сортировки товаров

sort_order = product_id устроит?

в phpmyadmin ({DB_PREFIX} – ваш префикс)

UPDATE `{DB_PREFIX}product` SET `sort_order` = `product_id` WHERE `product_id` > '0'

[=== admin/model/catalog/product.php ===]


public function addProduct($data) {
$product_id = $this->db->getLastId();
// auto sort_order = product_id
$this->db->query("UPDATE " . DB_PREFIX . "product SET sort_order = '" . (int)$product_id . "' WHERE product_id = '" . (int)$product_id . "'");