Hello all,
In this post we will discuss various technical questions (Computer Science) and answers asked in KERALA PSC examinations like computer programmer, computer science lecturer etc.
Hope this will be helpful. :)
The questions were asked in Programmer (145/2015) post.
1. SCSI stand for :
(A) Small Computer Systems Interface
(B) Simple Component
Systems Interface
(C) Simple Computer Systems Interface
(D) Small Component Systems Interface
Answer A
·
SCSI stands for Small Computer System Interface (SCSI)
·
It is a set of interface standards for attaching printers,
disk drives, scanners and other peripherals to computers.
·
SCSI is pronounced as "skuzzy"
2. Which of the following is a logical extension of
multiprogramming?
(A) Multi processing
(B) Multitasking
(C) Real time processing
(D) Distributed processing
Answer B
Remember these terms:
Multiprogramming
|
- One or more programs reside in main memory.
- Only one job is executed at a time.
- When current job is blocked or terminated next job is picked.
|
Multitasking
|
- Extension of multiprogramming.
- Multiple jobs are executed at same time by switching between
them.
|
Multiprocessing
|
- More than one physical processor is present.
- At a time more than one program get CPU for execution
|
Multithreading
|
Allows
multiple threads to run at same time.
|
Multiuser
|
Many users
can access at same time.
|
Real-time processing
|
A processing system that needs to be completed within a
fixed time frame. Real-time processing does not have to be fast
Eg: traffic lights, car engine control
|
Distributed computing
|
components are located on networked computers and they
communicate and coordinate their actions by passing messages
|
3. Which among the following is not an example of a Java
wrapper class?
(A) Char
(B) Integer
(C) Boolean
(D) Byte
Answer A
Wrapper class in java provides the mechanism to convert
primitive into object and object into primitive.
Autoboxing: convert primitive to object
Unboxing: Convert object to primitive
Java has eight wrapper classes: Boolean, Character, Byte, Short, Integer, Long, Float and Double
4. Which one of the following is not an ACID property?
(A) Atomicity
(B) Consistency
(C) Isolation
(D) Dependency Preservation
Answer D
A DBMS should obey ACID properties to make the transactions
correct.
ACID properties stand for Atomicity, Consistency, Isolation
and Durability
ACID property
|
Definition
|
Responsibility of
|
Atomicity
|
Either all tasks of the transaction are completed in the
database, or none are.
|
Recovery manager /Transaction manager
|
Consistency
|
Execution of a transaction must preserve the consistency
of the database.
Eg: if a faulty money transfer program credits an amount
less than it debited, the DBMS cannot detect it.
|
Users/ user programs.
|
Isolation
|
Each transaction will be executed as if it is the only
transaction in the system.
|
Concurrency control
|
Durability
|
The database should hold all its latest updates even if
the system fails.
|
Recovery manager
|
5. Which among the following sorting method is also known as
Bucket sorting?
(A) Radix sort
(B) Heap sort
(C) Merge sort
(D) Quick sort
Answer A:
·
The initial pass of both RadixSort and
BucketSort is exactly the same.
·
The elements put in buckets of incremental
ranges (e.g. 0-9, 10-19, ... 90-99)
·
In the next pass, however, BucketSort sort these
'buckets' and appends sorted buckets into one array. However, RadixSort appends
the buckets without further sorting and 're-buckets' it based on the second
digit of the numbers.
·
Hence, BucketSort is more efficient for 'Dense'
arrays,
·
RadixSort can handle sparse arrays well.
6. Which one of the following key is called the minimal
super key?
(A) Candidate key
(B) Super key
(C) Primary key
(D) None
Answer A
• Candidate
key: A set of fields that can uniquely identify a tuple in a relation.
• Super-key:
A set of fields in which at least one member is a candidate key.
• Primary
key: One of the candidate keys which administrator has been selected to
identify a tuple.
Unique key: The fields should not have duplicate values in
same table. It can have null values.