what i do for inventory control is on the eCart Object i create a new field wich i called Stack then on the Calculations panel i added a new calculation called substractions and placed this formula:
[Stack] - [Quantity] and the output was number so it should be kind of ([substractions] = [Stack] - [Quantity]), then on the product page where i have the add to cart i bind the products stack from the database to the stack column, and after the transaction is done if aproved from credit card, i use a page where i use the display manager again for printing the recipie or bill, but here i have a hidden php code wich i place next to
<p class="eC_ItemLabel"><?php echo $Ecart->DisplayInfo("Name"); ?>
i put
<?php
$FinalStack = $Ecart->DisplayInfo("substractions");
$idProduct = $Ecart->DisplayInfo("idPro");
mysql_select_db($database_XX, $YYYY);
$query_substractions = "UPDATE products SET stock = $FinalStack WHERE idPro = $idProduct" ;
$substractions = mysql_query($query_substractions, $YYYY) or die(mysql_error());
?>
so when this page loads it discounts and updates my stacks.
Hope this helps
