Better sql construct in sales/includes/db/sales_order_db.inc

diff --git a/sales/includes/db/sales_order_db.inc b/sales/includes/db/sales_order_db.inc
index d144995d7a70881b1bfcdc25b1b5652942dd66f4..f2c62840cc8d7fb7ef9c34789a6136a0295b3d9d 100644 (file)
--- a/sales/includes/db/sales_order_db.inc
+++ b/sales/includes/db/sales_order_db.inc
@@ -642,14 +642,11 @@ function last_sales_order_detail($order, $field)
 {
         $sql = "SELECT $field
             FROM ".TB_PREF."sales_order_details d
-            WHERE order_no =
-            (SELECT order_no FROM ".TB_PREF."sales_orders o
+            LEFT JOIN " .TB_PREF."sales_orders o on d.order_no=o.order_no
             WHERE debtor_no=" . db_escape($order->customer_id) . "
-            ORDER BY order_no DESC LIMIT 1)
-            ORDER BY d.id DESC LIMIT 1";        
+            ORDER BY d.id DESC LIMIT 1";
 
         $last_query=db_query($sql, "Could not retrieve last order detail");
         $row = db_fetch_row($last_query);
         return $row == false ? false : $row[0];
 }
-