how to model discount on items in a database?

Question

I am building an ecommerce site and would like to offer discounts on certain items for a limited time.

My Product table (MySQL) looks like this:

Product
    -         


        

Answer 1

You might consider adding a beginning timestamp and ending timestamp to your Deals table. That way, you can check to make sure the current date is between the start and end dates for the deal.

Your Deals table doesn't really need a dealID - it could be keyed with the productID and the start date of the discount. Also, depending on how high the price could be for a given item, remember to make your discount field something sufficiently precise (something like DECIMAL 12,8).

If it were me, I would actually leave price off of the Product table and create a ProductPricing table instead of creating a Deals table. That ProductPricing table would consist of the productID and a starting timestamp as the key fields, then also have an ending timestamp to indicate when that price changed. And, of course, the price of the item.