在一个表中合并两个实体

Question

I am making a thesis repository, and I came across another situation. I have 3 user levels, admin, staff and guest. I have this ERD diagram below. Situation: A user can be a student, admin or staff. However, one feature of this web app is to search theses by authors. Also, a user with admin / staff privilege upload thesis. Question: Can I consolidate student and other user privilege information in one table? Say like, all info will be stored in one table called users? Thanks in advance

InitialERD

Answer 1

A. If a user can have multiple privileges for an instance both a student & staff. Then you should have a user table with a one to many relationship with a user privilege table. User privilege table will contain the user privileges like student, guest, admin etc.

B. If a user will have exactly one privilege then you can include that within the user table as a field/column String privilegeKind;