Keeping data in a previous record
I'm creating an application. There are 3 different tables:
1. Clients (C-ID) - 2. Products (P-ID) en 3. Combination (COMBI-ID)
In the productstable I have only one record, containing the name of the products, their prices and a date-field.
Because I have only one record, all the fields ard global.
In the Combinationtable I have all the clients and the products they have used and the price the have paid.
The price is coming from the Productstablepricelist.
The problem is that when I change a price in the pricelist of the productstable, the prices in all the records of the Combinationtable are replaced by the new price, also the previous records.
How can I keep the old price in the previous records of the Combinationtable?