I need some help in understanding the difference between SKUs and UPCs. You told me you populate the SKU in WooCommerce with the unique identifier from the point of sale system, which is used as the Integration ID. However, isn't that the same thing as a UPC?
Think of the SKU as the unique identifier that connects the POS system to WooCommerce. In computer-speak, this can be a GUID, or any value that uniquely identifies that product. This number is unique for every variant of the product as well. Therefore, if a product came in 3 different sizes and 3 different colors, then it would have 9 unique numbers. WooCommerce has an SKU field for every product and every product variation.
UPCs are those barcodes you find on every product that gets scanned at the register. While UPCs generally don’t change, they can, and occasionally do. Additionally, while UPCs are very helpful when selling your products on marketplaces like Amazon, they are not required. Many retailers don’t even bother with UPCs if they don’t need them in-store, or for other selling channels. As mentioned above, WooCommerce does not have a field for UPCs, although with our technology, it’s easy for us to create and map to it.
For these reasons, UPCs make poor “Integration IDs”.