@yaniv14 Thanks for the answer.
In the old PS-Shop I never tried that. I have a list of over 9000 products from a supplier. For the articles, one or more suitable products with the article number are listed in some columns. I have always taken only items I selected. Now I consider creating a separate shop for this complete range of jewelery.
First of all, I assume that I have to do the data import 2 times so that the articles appear at all only once in the shop and then additionally an import with appropriate products. An assignment with the article number would be the easiest in this case. Otherwise I would have to look for a suitable formula, so that the article numbers get the right product id.