timo Is it of importance for the buyer to know what customer ID the seller has given him? Why does it have to be in the e-invoice? In your first post you write that this is your own requirement. Can you perhaps explain in more detail why this is important for you?
We often have several customers within the same institution/company, sometimes even with similar names, which can lead to confusion. So a unique customer ID is the easiest way for us identify and address customers reliably. However, we dont’t expect our customers to give this number when paying an invoice. So for us, it’s not really required in the e-invoice, it just needs to be on the (PDF) invoice somewhere (ideally close to the invoice number).
OTOH, it would be very important for us that this customer ID is persistently stored with the customer, because otherwise, there’s no point in an ID. Given your generic text field approach, probably the only way to make this persistent would be an additional line in the customer address text field. But that’s not where it visually belongs in the PDF (it’s usually close to the invoice number). So you would have to suppress it in the address (just like the email address) and allow to print it elsewhere (using a variable). But if you have to identify this line anyway, there’s no reason to not put it in the BT-46 XML field, too.
Looking into the future, maybe some day we’ll search the XML data and not the PDFs to find a specific customer. Then, of course, it would be bad if the customer ID was missing in the (earlier) XML data.
On a general note, I’m surprised that the customer ID isn’t regarded as a matter of course. As a consumer, since my teenage years I have been used to being assigned a customer ID each and every time I placed a mail order or later internet order with a company for the first time and often was also expected to give this ID when paying or asking for service.
This may have become less usual now that internet orders are most often coupled with a customer account which kind of replaces the customer ID. But that varies. So, I don’t have a customer ID at amazon, but I do have a customer ID at Conrad (one of Europe’s largest vendors for electronic components), although I have a customer account with both companies.
