$where = [];
$where[] = $write->quoteInto('request_type=?',$request_type);
$where[] = $write->quoteInto('shipping_id =?', $shipping_id);
$where[] = $write->quoteInto('status =?', 0);
$write->update('freeze_requests'
    ,['status'=>1
    ,'approved_by'=>$userId
    ,'approved_on'=>Mage::getModel('core/date')->gmtDate('Y-m-d H:i:s')]
    ,$where
);