I'm having a heck of a time keeping the totals on my invoice current. It is a standard clients/products/invoice/lineitem ERD.
So lineitems (from the LINEITEMS table) are generated and populated with information from both the clients and the products to do calculations.
My invoice total field on the INVOICE table uses a summary field from the LINEITEMS table and adds it to a tax field that is on the INVOICE table. That tax field is a calculation based on if tax is to be applied (radio button).
I figure the problem is with the TAX field needing to updated constantly but I am not sure the most eloquent (simple) way to achieve that.
any thoughts or ideas would be greatly appreciated