ช่วยดูให้หน่อยค่ะ แก้ไขราคาขายแล้วกดคำนวณให้ราคารวมเปลี่ยน แล้วค่อย update ราคาลงฐานข้อมูลค่ะ

<form name="form2" method="post" action="test.php">
                    <table width="318" height="24" border="0" cellpadding="0" cellspacing="0">
                      <tr>
                        <td align="center" bgcolor="#FFDB6F"><span class="style10">แก้ไขราคาขายของกระเช้าสินค้า</span></td>
                      </tr>
                    </table>
                    <br />
                    
                    <table width="804" border="0" cellpadding="3" cellspacing="01" bgcolor="#000000">
                      <tr>
                        <td width="46" align="center" bgcolor="#FFFFFF"><span class="style8">ลำดับ</span></td>
                        <td width="76" align="center" bgcolor="#FFFFFF"><span class="style8">รหัส</span></td>
                        <td width="171" align="center" bgcolor="#FFFFFF"><span class="style8">รายการ</span></td>
                        <td width="94" align="center" bgcolor="#FFFFFF"><span class="style8">ประเภท</span></td>
                        <td width="75" align="center" bgcolor="#FFFFFF"><span class="style8">ขนาด</span></td>
                        <td width="74" align="center" bgcolor="#FFFFFF"><span class="style8">จำนวน</span></td>
                        <td width="113" align="center" bgcolor="#FFFFFF"><span class="style8">ราคาขาย</span></td>
                        <td width="97" align="center" bgcolor="#FFFFFF"><span class="style8">ราคารวม</span></td>
                      </tr>
              <? 
		   $select = "SELECT * FROM productdetail , material , product , material_type
                               WHERE product.p_id = productdetail.p_id  
                               AND productdetail.m_id = material.m_id
                               AND material_type.mt_id = material.mt_id
                               AND product.p_id = '$p_id' 
                               ORDER BY productdetail.pd_id ASC";
			                    $no = 1;
			        $result = mysql_query($select);
			       while($read = mysql_fetch_array($result)){
	
	     ?>
                      <tr>
                        <td align="center" bgcolor="#FFFFFF"><span class="style8">
                          <?=$no++?>
                        </span></td>
                        <td align="center" bgcolor="#FFFFFF"><span class="style8">
                          <?=$read['m_id']?>
                        </span></td>
                        <td align="center" bgcolor="#FFFFFF"><span class="style8">
                          <?=$read['m_name']?>
                        </span></td>
                        <td align="center" bgcolor="#FFFFFF"><span class="style8">
                          <?=$read['mt_name']?>
                        </span></td>
                        <td align="center" bgcolor="#FFFFFF"><span class="style8">
                          <?=$read['m_size']?>
                        </span></td>
                        <td align="center" bgcolor="#FFFFFF"><span class="style8">
                          <?=$read['m_qty']?>
                        </span></td>
                        <td align="center" bgcolor="#FFFFFF">
                        <input name="m_price" type="text" id="m_price" value="<? echo number_format($read['m_price'],2)?>" size="10" /></td>
                      <td align="center" bgcolor="#FFFFFF"><span class="style8"><? echo number_format($read["m_price"]*$read["pd_amount"],2) ?></span></td>
                      </tr>
                        
                        <?
							
							 $total=($read["m_price"]*$read["pd_amount"])+$total;
							 $total2=$total+150;
							 
							  
				         ?>
                            <? }?>
                                               
                      <tr>
                        <td colspan="6" rowspan="2" bgcolor="#FFFFFF">&nbsp;</td>
                        <td align="center" bgcolor="#FFFFFF"><span class="style8">ค่าจัด</span></td>
                        <td align="center" bgcolor="#FFFFFF"><span class="style8">150 บาท</span></td>
                      <tr>
                        <td align="center" bgcolor="#FFFFFF"><span class="style8">รวมราคาทั้งสิ้น</span></td>
                        <td bgcolor="#FFFFFF"> <span class="style8"> <? echo number_format($total2,2) ?> บาท</span></td>
                    </table>
                 
                    <br />
                    <br />
                    <input type="submit" name="Submit" id="Submit2" value="คำนวณ" />
                    <input type="submit" name="Sumit2" id="Sumit" value="แก้ไข" />
                  </form>