The Shipping Discount Price Group, discounted products only, gives a customer discounted shipping for only certain items in their order.
The fields for this Price Group are exactly the same for the Shipping Discount (Entire Order) Price Group. The only difference, is that instead of giving the customer a shipping discount on everything in their basket, they only get a discount on “eligible” items in their basket.
Basket items are eligible for a shipping discount if they meet the following conditions:
It's important to note that because of the way this Price Group is set up, it can be resource intensive. For example, let's say a customer has three items in their basket, two of which get a 50 percent discount off shipping.
Miva will make three API calls to the shipping carrier in order to calculate shipping. It will make two calls to calculate shipping for the two discounted shipping items, and then a third call for the entire basket. Miva will then discount the shipping for the qualifying products by 50 percent, and subtract that amount from the total cost of shipping the entire basket.
This is important because if your shopper has a basket with 10 discounted items, there would be 11 API calls to the shipping carrier, which would take some time and slow down the checkout process.