Hi all..can somebody tell me how to do this..

I have two tables, po and po_item..
There is one to many relationship.

PO
po_id
po_no
po_date

po_item
item_id
po_no
item
qty
unit_price
total

Now i want to display all data from po and a total price for every po that i sum from po_item.I mean sum total from po_item group by po_no.

This is what i have done so far..
PHP Code:
<?
$query = "SELECT * FROM po";
$result=mysql_query($query);
    if (!$result)
            die("<p>ERROR number". mysql_errno(). ": ".mysql_error() ."</p>");
            $num_results=mysql_num_rows($result);                             
?>
PHP Code:
<?
// Display data

<table width="95%" border="1" align="center" cellpadding="3" cellspacing="0" class="title" bordercolor="#CCCCCC">
 <tr>
      <td align="center" colspan="9">&nbsp;&nbsp;</td>
  
  </tr>
  <tr> 
  <td width="19%" align="center"> P.O NO </td>
  <td width="11%"><font face="Tahoma">DATE</font></td><td> TOTAL PRICE </td>               
</tr>                
                
    <? for ($i=0; $i < $num_results; $i++){
    $row=mysql_fetch_array($result);
    ?>        
    <tr>                                        
            <td><? echo $row['po_no']?></td>
           <td><? echo $row['po_date']</td> 
           <td>&nbsp;</td>                                                         
    </tr>
    <? } ?>
    </table>
Can someone give me an idea or way how to do this..thanks in advance