Select list need to pass a value to collect information based on a value on another page

Question

i have a product-detail.php page that is then sent to a cart.php i have a number of tables that are all joined and show in the statement below. the results are displayed on the detail page
$var1_rsProduct = "-1";
if (isset($_GET['productID'])) {
  $var1_rsProduct = $_GET['productID'];
mysql_select_db($database_beau, $beau);
$query_rsProduct = sprintf("SELECT * FROM beauAW13_Cat, beauAW13_products, beauAW13_Stock, beauAW13_SizeList WHERE beauAW13_products.catID = beauAW13_Cat.catID AND beauAW13_products.ProductID = beauAW13_Stock.ProductID AND beauAW13_Stock.SizeID = beauAW13_SizeList.SizeID AND beauAW13_products.ProductID = %s AND beauAW13_Stock.Stock != 0 ", GetSQLValueString($var1_rsProduct, "int"));
$rsProduct = mysql_query($query_rsProduct, $beau) or die(mysql_error());
$row_rsProduct = mysql_fetch_assoc($rsProduct);
$totalRows_rsProduct = mysql_num_rows($rsProduct);
i have a select list that needs to show the sizes.this is shown below
<select name="select" id="select">
                <?php
do { 
?>
                <option value="<?php echo $row_rsProduct['StockID']; ?>"><?php echo $row_rsProduct['Size']?></option>
                <?php
} while ($row_rsProduct = mysql_fetch_assoc($rsProduct));
  $rows = mysql_num_rows($rsProduct);
  if($rows > 0) {
      mysql_data_seek($rsProduct, 0);
            $row_rsProduct = mysql_fetch_assoc($rsProduct);
?>
              </select>
it is currently passing the value of <?php echo $row_rsProduct['StockID']; ?>
which is ok as this is a totally unique number so on the cart page i need to get all the size information from that stockID
here is an example:-
i have used a stockID of 355
on the cart.php the stockID is echoed out as 355 and the size is echoed out as 355 which is what i would expect.
the stock table looks like this
StockID | ProductID | SizeID  |  Stock
  355   |    582    |   14    |    5
so
ProductID is blue jumper
Stock id is unique number
SizeID = 14 = once size
Stock = 5 in stock
so i need to in the cart say
355 = 14 = one size
i can then echoe out the correct size as one size and not 355
i really hope someone can help
thanks

Answer 1

Thanks for everyone advise. I managed to get it working
I sent the stockID on;y to the cart page, made a new variable based on the stockID the made a query and got all the information based on the new stockID variable
<?php
$newStockID = $XCart_StockID = ${$XCName}["contents"][0][$XCart__i];
mysql_select_db($database_beau, $beau);
$query_rsSize = "SELECT * FROM beauAW13_SizeList, beauAW13_Stock WHERE beauAW13_Stock.SizeID = beauAW13_SizeList.SizeID AND beauAW13_Stock.StockID = '$newStockID'";
$rsSize = mysql_query($query_rsSize, $beau) or die(mysql_error());
$row_rsSize = mysql_fetch_assoc($rsSize);
$totalRows_rsSize = mysql_num_rows($rsSize);
                          ?>
select list
<option value="<?php echo $row_rsProduct['StockID']; ?>"><?php echo $row_rsProduct['Size']?></option>