GATE CS 2021 : National champion Quiz-3 (App update required to attempt this test) for GATE & PSU CS Exams

Question 1

Consider the following relations:
Student (snum: integer, sname: string, major: string, level: string, age: integer)
Class (name: string, meets at: string, room: string, ﬁd: integer)
Enrolled (snum: integer, cname: string)
Faculty (ﬁd: integer, fname: string, deptid: integer)
Consider the following SQL statements:
SELECT DISTINCT S.sname
FROM Student S
WHERE S.snum IN
(SELECT E.snum
FROM Enrolled E
GROUP BY E.snum
HAVING COUNT (*) >= ALL (SELECT COUNT (*)
FROM Enrolled E2
GROUP BY E2.snum))
What is the output of the following Query?

Question 2

Consider the following relational schema:

Suppliers (sid:integer, sname:string, city:string, street:string)

Parts (pid:integer, pname:string, color:string)

Catalog (sid:integer, pid:integer, cost:real)

Assume that, in the suppliers relation above, each supplier and each street within a city has a unique name, and (sname, city) forms a candidate key. No other functional dependencies are implied other than those implied by primary and candidate keys. Which one of the following is TRUE about the above schema?

Question 3

Which of the following is true?

Question 4

Consider the relational algebra query over Enroll (Sid, Cid, grade) relation:

What is the output return by the above query?

Question 5

Consider an Entity-Relationship (ER) model in which entitysets E₁ and E₂ are connected by an m : n relationship R₁₂. E₁ and E₃ are connected by a 1 : n (1 on the side of E₁ and n on the side of E₃) relationship R₁₃.
E₁ has two single-valued attributes a₁₁ and a₁₂ of which a₁₁ is the key attribute. E₂ has two single- valued attributes a₂₁ and a₂₂ of which a₂₁ is the key attribute. E₃ has two single-valued attributes a₃₁ and a₃₂ of which a₃₁ is the key attribute. The relationships do not have any attributes.
If a relational model is derived from the above ER model, then the minimum number of relations that would be generated if all the relations are in 3NF is_________.

Question 6

Which statement/statements are false -

A) Number of prime key always same to primary key

B) It is forced that only a super key can identify an attribute uniquely in 3.5NF

C) R(ABCD), ABC->D, D-> B, partial dependency presents in this relation R

D) Super key establishes connection between two tables.

Which statement/statements are false -

Question 7

The following switching functions are to be implemented using a decoder:

f₁ = ∑m(1, 2, 4, 8, 10, 14) f₂ = ∑m(2, 5, 9, 11) f₃ = ∑m(2, 4, 5, 6, 7)

The minimum configuration of decoder will be __________

Question 8

If F and G are two Boolean functions with n variables. If function G is exactly true for x input combinations and function F covers G. Then what can be the maximum possible number of covering functions F?

Question 9

Consider the following circuit diagram.

What will be a minimal expression for function F, considering I₁ and I₀ is connected to C.

Question 10

Let a, b, c, d, e, f are the Boolean variable and F is the Boolean function such that F = a xor b xor c xor d xor e xor f. For how many different inputs of a, b, c, d, e, f, the function F takes the value 1 _____________?

Question 11

Which of the following flip-flops is used to avoid race around problem?

Question 12

Following the state diagram shown clocked sequential circuit:

How many states the sequential circuit has?