Added * as a valid char for orderBy and groupBy

MysqliDb.php

@@ -713,7 +713,7 @@ class MysqliDb
     {
         $allowedDirection = Array ("ASC", "DESC");
         $orderbyDirection = strtoupper (trim ($orderbyDirection));
-        $orderByField = preg_replace ("/[^-a-z0-9\.\(\),_`]+/i",'', $orderByField);
+        $orderByField = preg_replace ("/[^-a-z0-9\.\(\),_`\*]+/i",'', $orderByField);
 
         // Add table prefix to orderByField if needed.
         //FIXME: We are adding prefix only if table is enclosed into `` to distinguish aliases
@@ -746,7 +746,7 @@ class MysqliDb
      */
     public function groupBy($groupByField)
     {
-        $groupByField = preg_replace ("/[^-a-z0-9\.\(\),_]+/i",'', $groupByField);
+        $groupByField = preg_replace ("/[^-a-z0-9\.\(\),_\*]+/i",'', $groupByField);
 
         $this->_groupBy[] = $groupByField;
         return $this;