update multiple row prices

[vinpkl]

hi all

i m trying to update multiple rows which contain product price.

when i update the price of last product to 450.00 then all product prices get updated as 450.00

when i update the price of 1st or second product then no product price gets updated.

This is update script

if(isset($_REQUEST['submit'])) {    

 $msg = (string) '';   

 $prid=array();   

 $new_price=$_REQUEST['new_price'];
 $prid=$_REQUEST['prid'];   

 $count=count($prid);    

 for($i=0;$i<$count-1;$i++) {      

 $del_id = $prid[$i];          

 $qry2 = "update product_table set price='$new_price' where product_id =$del_id";     

 echo $qry2;
 $result2 = mysql_query($qry2);      

 if($result2 && mysql_affected_rows() > 0) {       

 $msg .= "Product ( ".$del_id." ) updated Successfully<br />";
 } 
 else {       

 $msg .= "Error updating product $del_id<br />";     

 }  } } 

This is display script

<?php
$qry="select * from product_table where dealer_id=$dealer_id and sub_catg='$sub_catg' order by product_id asc";
$result = mysql_query($qry);
if(mysql_num_rows($result)>0)
{
while($row=mysql_fetch_array($result))
{
echo "<tr>";
echo "<td>". "<input type='hidden' name='prid[]' id='prid[]' value=". $row['product_id']. ">"."</td>";
echo "<td valign=top>". $row['product_id'] . "</td>";
echo "<td valign=top>". $row['product_name'] . "</td>";
echo "<td valign=top>". $row['price'] . "</td>";
echo "<td valign=top>"."<input type='text' name='new_price' id='new_price'>" . "</td>";
echo "</tr>";	
}
echo "<td valign='top' colspan='9'><input name='submit' type='submit' value='Update Prices' />";
echo "<input type='hidden' name='prid[]' value=".$row2['product_id']." />";
echo "</td>";
}
?>

vineet

[Bjom]

for($i=0;$i<$count-1;$i++) {       

$del_id = $prid[$i];           

$qry2 = "update product_table set price='$new_price' where product_id =$del_id";      

echo $qry2; 
$result2 = mysql_query($qry2);     

-->

for($i=0;$i<$count-1;$i++) {           

$qry2 = "update product_table set price='$new_price[$i]' where product_id =$prid[$i]";      

echo $qry2; 
$result2 = mysql_query($qry2);

This solves one problem (updating all prices to one value). Not sure about the other...