PHP Mysql pivot table

PHP Mysql pivot table

I am using the Following code to return a purchase details.That displays
the result like this
Name Qty Value
Product1 30 1000
Product1 45 2000
Product2 20 1500
Product2 25 3000
How can sum up the pdt's quantity and value And display like this
Name Qty Value
Product1 75 3000
Product2 45 4500
Total 120 7500
With Select Where clause.
$result = mysql_query("SELECT pdtname,pack,qty,value FROM ist WHERE
chemistcode='3121' AND chemistcode='3020' AND companycode =
$companycode");
echo "<table id=customers>
<tr>
<th>Product</th>
<th>Pack</th>
<th>Qunatity</th>
<th>Value</th>
</tr>";
while($row = mysqli_fetch_array($result))
{
echo "<tr>";
echo"<td>" . $row['pdtname'] . "</td>";
echo"<td>" . $row['pack'] . "</td>";
echo"<td>" . $row['qty'] . "</td>";
echo"<td>" . $row['value'] . "</td>";
echo "</tr>";
}
echo "</table>";