I kindly ask for your support because I have to achieve something that seems to be simple but I just can't figure it out how to do it.
Mainly, I have two columns. The first one contains some parent codes, the second one contains some child codes which can consequently become parent codes for other child codes. And so on.
Having this in mind, I want to create a hierarchy like the one form the example file (see attachment). The example file was created manually with a minimum number of records but the final database can be way bigger.
Thank you in advance for your support!