ISRO CS 2017

Question 71

The minimum number of stacks needed to implement a queue is

• 3

• 1

• 2

• 4

Question 72

Type IV JDBC driver is a driver

• which is written in C++
• which requires an intermediate layer
• which communicates through Java sockets
• which translates JDBC function calls into API not native to DBMS

Question 73

Which of the following is not true with respect to deadlock prevention and deadlock avoidance schemes?

• In deadlock prevention, the request for resources is always granted if resulting state is safe
• In deadlock avoidance, the request for resources is always granted, if the resulting state is safe
• Deadlock avoidance requires knowledge of resource requirements a priori
• Deadlock prevention is more restrictive than deadlock avoidance

Question 74

Quick sort is run on 2 inputs shown below to sort in ascending order

A. 1, 2, 3……n
B. n, n – 1, n – 2 …… 1

Let C1 and C2 be the number of comparisons made for A and B respectively. Then

• C1 > C2

• C1 = C2

• C1 < C2 
  

• Cannot say anything for arbitrary n

Question 75

Assume that Source S and Destination D are connected through an intermediate router R. How many times a packet has to visit the network layer and data link layer during a transmission from S to D?

• Network layer – 4 times, Data link layer – 4 times
• Network layer – 4 times, Data link layer – 6 times
• Network layer – 2 times, Data link layer – 4 times
• Network layer – 3 times, Data link layer – 4 times

Question 76

Consider the set of activities related to e-mail A : Send an e-mail from a mail client to mail server B : Download e-mail headers from mail box and retrieve mails from server to a cache C : Checking e-mail through a web browser The application level protocol used for each activity in the same sequence is

• SMTP, HTTPS, IMAP
• SMTP, POP, IMAP
• SMTP, IMAP, HTTPS
• SMTP, IMAP, POP

Question 77

Using public key cryptography, X adds a digital signature σ to a message M, encrypts (M,σ) and sends it to Y, where it is decrypted. Which one of the following sequence of keys is used for operations?

• Encryption : X’s private key followed by Y’s private key. Decryption : X’s public key followed by Y’s public key.
• Encryption : X’s private key followed by Y’s public key; Decryption : X’s public key followed by Y’s private key
• Encryption : X’s private key followed by Y’s public key; Decryption : Y’s private key followed by X’s public key.
• Encryption : X’s public key followed by Y’s private key; Decryption : Y’s public key followed by X’s private key.

Question 78

Which of the following related to snowflake schema is true?

• Each dimension is represented by a single dimensional table
• Maintenance efforts are less
• Dimension tables are normalised
• It is not an extension of star schema

Question 79

Consider a table that describes the customers :

Customers(custid, name, gender, rating)

The rating value is an integer in the range 1 to 5 and only two values (male and female) are recorded for gender. Consider the query “how many male customers have a rating of 5”? The best indexing mechanism appropriate for the query is

• Linear hashing
• Extendible hashing
• B+ Tree
• Bit-mapped hashing