21. What deletes the entire file except the file structure?
(A) ERASE (B) DELETE
(C) ZAP (D) PACK
22. Which command classes text file, which has been created using “SET ALTERNATIVE” <FILE NAME> “Command” ?
(A) SET ALTERNATE OFF
(B) CLOSE DATABASE
(C) CLOSE ALTERNATE
(D) CLEAR ALL
23. Data security threats include
(A) privacy invasion
(B) hardware failure
(C) fraudulent manipulation of data
(D) encryption and decryption
24. Which of the following statements is true, when structure of database file with 20 records is modified?
(A) ? EOF ( ) Prints T
(B) ? BOF ( ) Prints F
(C) ? BOF ( ) Prints T
(D) ? EOF ( ) Prints F
25. The SQL Expression
Select distinct T. branch name from branch T, branch S where T. assets > S. assets and S. branch-city = DELHI, finds the name of
(A) all branches that have greater asset than any branch located in DELHI.
(B) all branches that have greater assets than allocated in DELHI.
(C) the branch that has the greatest asset in DELHI.
(D) any branch that has greater asset than any branch located in DELHI.
26. Dijkestra banking algorithm in an operating system, solves the problem of
(A) deadlock avoidance (B) deadlock recovery
(C) mutual exclusion (D) context switching
27. The multiuser operating system, 20 requests are made to use a particular resource per hour, on an average the probability that no request are made in 45 minutes is
(A) e-15 (B) e-5
(C) 1 – e-5 (D) 1 – e-10
28. On receiving an interrupt from an I/O device, the CPU
(A) halts for predetermined time.
(B) branches off to the interrupt service routine after completion of the current instruction
(C) branches off to the interrupt service routine immediately.
(D) hands over control of address bus and data bus to the interrupting device.
29. The maximum amount of information that is available in one portion of the disk access arm for a removal disk pack (without further movement of the arm with multiple heads)
(A) a plate of data (B) a cylinder of data
(C) a track of data (D) a block of data
30. Consider a logical address space of 8 pages of 1024 words mapped with memory of 32 frames. How many bits are there in the physical address?
(A) 9 bits (B) 11 bits
(C) 13 bits (D) 15 bits