1
GATE AI 2025
MCQ (More than One Correct Answer)
+2
-0

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
2
GATE AI 2025
MCQ (More than One Correct Answer)
+2
-0

Consider a database relation $R$ with attributes ABCDEFG , and having the following functional dependencies:

$$ \mathrm{A} \rightarrow \mathrm{BCEF} \quad \mathrm{E} \rightarrow \mathrm{DG} \quad \mathrm{BC} \rightarrow \mathrm{~A} $$

Which of the following statements is/are correct?

A
A is the only candidate key of R
B
A, BC are the candidate keys of R
C
A, BC, E are the candidate keys of R
D
Relation R is not in Boyce-Codd Normal Form (BCNF)