Is every lot ID unique?
Lot numbers are more unique than SKUs. Each SKU represents a unique product in your inventory. Each lot represents the receipt of a unique product at a specific point in time.
So if you receive 50 units of SKU 123 today, those units will all be assigned Lot1. Then if you receive 50 more units of SKU 123 tomorrow, those will all be assigned Lot2.
What's the difference between family data and SKU data?
Family data consists of the fields and attributes whose values stay the same for all SKUs within the family. Think of SKUs as individual members within the larger product family. Family data are details that the entire family shares--for example, your family probably shares the same last name and nationality. SKU data are details that may be unique to different members of the family--for example, you likely have a different first name, height, and weight than your siblings.
Likewise, say you have a set of men’s t-shirts from the same manufacturer with the same exact design. But they come in many different sizes and a few different colors. Brand, Product Name, Gender, and Category would be family data; Size and Color would be SKU data.
However, you have control over which data would be considered family data and which would be SKU data. These are not static settings. On RO’s PIM screen, family data resides on the left-hand side and SKU data on the right-hand side, also known as the SKU Grid.
From the PIM, you can drag-and-drop attributes from the left to right (and vice versa), changing the attributes from family data to SKU data (and vice versa) at will (note that the attribute must be configured to allow SKU associations first; read the article “Build New Product Attributes”). Simply click on the attribute name to drag it over either way.