diff --git a/install-dev/upgrade/php/add_order_reference_in_order_payment.php b/install-dev/upgrade/php/add_order_reference_in_order_payment.php
index 1ce631c1f..75b5d0782 100644
--- a/install-dev/upgrade/php/add_order_reference_in_order_payment.php
+++ b/install-dev/upgrade/php/add_order_reference_in_order_payment.php
@@ -27,47 +27,49 @@
 function add_order_reference_in_order_payment()
 {
 	$res = true;
-	$payments = Db::getInstance()->executeS('
+	$payments = Db::getInstance()->query('
 	SELECT op.id_order_payment, o.reference
 	FROM `'._DB_PREFIX_.'order_payment` op
 	INNER JOIN `'._DB_PREFIX_.'orders` o
 	ON o.id_order = op.id_order');
 	
-	if (!is_array($payments))
+	if (!is_object($payments))
 		return false;
 	
 	$errors = array();
-	
-	
 	// Populate "order_reference"
-	foreach ($payments as $payment)
+	while ($payment = Db::getInstance()->nextRow($payments))
 	{
-		$res = Db::getInstance()->execute('
-		UPDATE `'._DB_PREFIX_.'order_payment`
-		SET order_reference = \''.$payment['reference'].'\'
-		WHERE id_order_payment = '.(int)$payment['id_order_payment']);
-		
-		if (!$res)
-			$errors[] = Db::getInstance()->getMsgError();
+		if(isset($payment['id_order_payment']))
+		{
+			$res = Db::getInstance()->execute('
+			UPDATE `'._DB_PREFIX_.'order_payment`
+			SET order_reference = \''.$payment['reference'].'\'
+			WHERE id_order_payment = '.(int)$payment['id_order_payment']);
+			if (!$res)
+				$errors[] = Db::getInstance()->getMsgError();
+		}
 	}
 	
 	if (count($errors))
 		return array('error' => true, 'msg' => implode('<br/>', $errors));
 
 	// Get lines to merge (with multishipping on, durring the payment one line was added by order, only one is necessary by cart)
-	$duplicate_lines = Db::getInstance()->executeS('
+	$duplicate_lines = Db::getInstance()->query('
 	SELECT GROUP_CONCAT(id_order_payment) as id_order_payments
 	FROM `'._DB_PREFIX_.'order_payment`
 	GROUP BY order_reference, date_add
 	HAVING COUNT(*) > 1');
 	
-	if (!is_array($duplicate_lines))
+	if (!is_object($duplicate_lines))
 		return false;
 
 	$order_payments_to_remove = array();
-	foreach ($duplicate_lines as $order_payments)
+	while ($order_payments = Db::getInstance()->nextRow($duplicate_lines))
 	{
-		$order_payments_array = explode(',', $order_payments['id_order_payments']);
+		$order_payments_array = array();
+		if(isset($order_payments['id_order_payments']))
+			$order_payments_array = explode(',', $order_payments['id_order_payments']);
 		// Remove the first item (we want to keep one line)
 		$id_order_payment_keep = array_shift($order_payments_array);
 		
@@ -84,6 +86,5 @@ function add_order_reference_in_order_payment()
 	
 	if (!$res)
 		return array('errors' => true, 'msg' =>  Db::getInstance()->getMsgError());
-	
 	return true;
 }