ขนาดวิดีโอ: 1280 X 720853 X 480640 X 360
แสดงแผงควบคุมโปรแกรมเล่น
เล่นอัตโนมัติ
เล่นใหม่
How can cName be null if its primary keyyyyyy
cName is a primary key for College relation and not in Student relation, it's capturing association in Student relation and there can be no association between a student and college so it could be NULL in Student relation.
How can cName be null if its primary keyyyyyy
cName is a primary key for College relation and not in Student relation, it's capturing association in Student relation and there can be no association between a student and college so it could be NULL in Student relation.