How to : Computed field

Hi everybody,

• I've a dataTable mapped on a postgresql table, with 2 columns defined (i.e. Product_qty and Product_price)
• i've an Editor mapped on the dataTable object and it works fine

Now i need to add a third column which will be a computed column with Product_qty * Product_price formula and when user change (inline) a value in, say, Product_price, the formula is recomputed !

I'm searching for such function and find no solution !

Coould someone help me ?

Thanks Oliver