diff --git a/htdocs/commande/class/commande.class.php b/htdocs/commande/class/commande.class.php
index db122861052..abfd41a9c3f 100644
--- a/htdocs/commande/class/commande.class.php
+++ b/htdocs/commande/class/commande.class.php
@@ -1356,6 +1356,7 @@ class Commande extends CommonObject
             $row = $this->db->fetch_row($resql);
             return $row[0];
         }
+        else dol_print_error($this->db);
 	}
 
 	/**