Replete Rows Collect Together In Gidview

i want to view same named( ex: first_name) only one time and wanted to add repeated column to together

i want to show users and it related roles in one line

join query

$criteria = new CDbCriteria;

  $criteria->select = 't.id, a.itemname as role, t.first_name, t.username, t.email, t.address, t.tele';


  $criteria->join = 'LEFT JOIN authassignment a ON t.id = a.userid LEFT JOIN authitem m ON m.name = a.itemname';


 // $criteria->group = 't.first_name';


  $criteria->order ='t.id';