Ellipse
Dashed ellipse
Rectangle
Diamond
Triangle
Direct
Hash
Random
Sequential
Join
Self Join
Outer Join
Equi Join
BankAccount Num is a candidate key.
Registration Num can be a primary key
UID is candidate key if all students are from same country.
If S is a super key such that S ∩ UID is NULL then S ∪ UID is also a super key.