OS, DBMS and computer networks practice set 1

Question 1

A deadlock needs four conditions. Which is NOT one of them?

Accepted Answer

Preemption

Question 2

Which scheduling algorithm can cause starvation of long processes?

Accepted Answer

Shortest Job First

Question 3

Thrashing in an operating system happens when:

Accepted Answer

The system spends most of its time swapping pages

Question 4

Which memory is volatile?

Accepted Answer

RAM

Question 5

ACID in databases stands for:

Accepted Answer

Atomicity, Consistency, Isolation, Durability

Question 6

Which key uniquely identifies a row and can be referenced by a foreign key in another table?

Accepted Answer

Primary key

Question 7

How many layers does the OSI model have?

Accepted Answer

7

Question 8

Which protocol resolves an IP address to a MAC address?

Accepted Answer

ARP

Question 9

TCP differs from UDP because TCP is:

Accepted Answer

Connection-oriented and reliable

Question 10

Which port does HTTPS use by default?

Accepted Answer

443

Question 11

What does DNS do?

Accepted Answer

Translates domain names to IP addresses

Question 12

A process differs from a thread because:

Accepted Answer

Processes have separate memory; threads of a process share memory

Question 13

Which page replacement algorithm can suffer from Belady's anomaly?

Accepted Answer

FIFO

Question 14

Which SQL isolation problem occurs when a transaction reads data that another uncommitted transaction has changed?

Accepted Answer

Dirty read

Question 15

What is the size of an IPv6 address?

Accepted Answer

128 bits

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