How to avoid unstored calculations
So I am rebuilding a small database we have. It basically stores invoices. There are 3 tables, Customers, Products and invoice line items. A customer buys a product, we show it via the invoiced line item and it auto calculates the price based on the current price in the Products table and displays that in the line items table.
The problem is two fold, it seems unstored calculations really slow down summaries and reports when we are using this database via FileMaker server via a remote network. And if a price changes, then old customer records change too. I want to price on the line item to reflect what the price was on that day it was created, not todays current price.
My understanding is by not using unstored calculations I'm better off in both areas. But the box that allows me to change this in my calculated look ups is greyed out because I'm referencing a related table. Is there a trick or work around I should know about?