You can do this with numbers. Customers start with 1, products start with 2, etc. This is a little annoying if you aim small (products are 200-299, but now yo

You can do this with numbers. Customers start with 1, products start with 2, etc. This is a little annoying if you aim small (products are 200-299, but now you have your 101st product), or design this scheme without realizing you need to add a 10th entity (or 100th), but it does mostly work.