I have a list of around 500k rows and I'm trying to fill in blanks under 'code' with unique values assoiated with the ID (product)
my picture shows product 1 will a null value and I need to fill it in with a new code, but it can't be a code already used by product 1. so my options are either ABC or GGG. I only need one value (ABC or GGG) and it doesn't mater which one. how can I do this?