calculation field with related tables
I need to get a calculation field with inputs of related tables, but I need to put it in a portal with others related fields.
I have one table called inventary and another called incomes. I put a portal with fields of inventary to complete an invoice. In "inventary table" I have de prices and productos, but I want to put PxQ, I mean, the total of the sell for each product, but the result is gotten only for the first input or line of the portal, and repits this number for the others lines.
Please if somebody can answer me in spanish would be much better for me.