I am setting up a db and need to set up a field (c_Balance) to show only payment made, no future payments...
I have two tables Plots and Payment (related).
On the Plot, I have fields amount (price for the plot) and a cBalance (Price - s_sumopayment).
I need to forecast payment, ie: When we sell the land, we now that the buyer will pay a certain amount everymonth...so we enter this amount on the payment field and set the date for the future.
How can I set the cBalance to show the balance only for the payment made?
Or do I need to change my structure?