I looked into this when I worked there almost 3 decades ago. It was originally the sample database for Microsoft Access, of course, and was the first of its kind. I surveyed pretty much all the database managers made for personal computers at the time, and it was always a pain in the neck to work up something like a usable sample set. It was inspired by (not copied from) customer lists, but of course extensively massaged and completely removing anything that might accidentally seem identifiable. Even back then Microsoft was high profile, so they made sure there was nothing that could get them into trouble. Putting it together was a fairly complex process with considerations for localization, fake city names that didn’t sound bad, somewhat realistic record count, etc.
