Sorry but this seems almost archaic to me. When I was a student we were assigned a number by the exam office that we wrote on our exams, then after the exams were corrected the exam office would send us back our result. It was quite simply putting in a middle-man that did the student <-> number mapping so that the people correcting the exams never saw any names.

Here, students can also view their graded exams online. There are some professors that don't do it out of fear of the exams questions being leaked. In that case, you'd go there in person, but you would definitely not be able to just go through the exams on your own until you find the right one. That would never pass data protection laws.