Consider the following two relations, named Customer and Person, in a…

GATE · 2025 · DA · Data Science & AI

Consider the following two relations, named Customer and Person, in a database:

Person (
    aadhaar CHAR(12) PRIMARY KEY,
    name VARCHAR(32));
Customer (
    name VARCHAR(32),
    email VARCHAR(32) PRIMARY KEY,
    phone CHAR(10),
    aadhaar CHAR(12),
    FOREIGN KEY (aadhaar) REFERENCES Person(aadhaar));

Which of the following statements is/are correct?

A.
aadhaar is a candidate key in the Customer relation
B.
phone can be NULL in the Customer relation
C.
aadhaar is a candidate key in the Person relation
D.
aadhaar can be NULL in the Person relation

Attempted by 21 students.

Explore the full course: Gate Guidance By Sanchit Sir