Discount Code (20% off) but only applicable to specific products...how?

We have a discount code form field on our basket page and have worked out how to apply blanket discounts to all products however our client has asked if only certain products can be discounted based on entry of a specific discount code.

This is confusing the heck out of me because if I select "Presence of an item in cart" and then enter the product code I'll need to do that with OR statements a heap of times won't I? Actually, won't that then apply the discount regardless of what else is in the cart?

Our product are database driven btw.

Would appreciate your advice on best solution for this. Also, how about a "Discounts" and "Charges" page on your website that details the formulas for this types of things?

Thank you
NJ

try creating another column in the cart object, eg product category.

if that particular category is in the cart, then apply the discount code

Thanks Craig for that idea. I have also struggled with how to do this. I wish there was a tutorial on all the options for the discounts. I have been learning by hit and miss. Each time I need a new variable, it takes a while to figure it out. Maybe this could be one of your tutorials?

Originally Said By: CraigR

  try creating another column in the cart object, eg product category.

if that particular category is in the cart, then apply the discount code  

If I do that the discount will be applied to the cart sub-total and we only want the discount to affect products which are marked for discount.

In the calcaulton settings, set it to be "based on items with a specific value"

for example:

Total of 'TotalPrice' where 'Category' has a value of '1' 'Times' '0.2'


That will apply a 20% discount on the subtotal of TotalPrice for items whose Category has a value of 1.