Ther relational schema R(X,Y, Z), there are functional dependencies: XZ,YZ, then belonging to the Primary attribute is ( ).
A、 X and Z
B、 X and Y
C、 X, Y, and Z
D、 Y and Z
发布时间:2025-05-25 10:19:30
A、 X and Z
B、 X and Y
C、 X, Y, and Z
D、 Y and Z