Computer (NCO)
This test contains computers and IT related questions for class 12.
Questions
Which operator is used to access a structure element using a pointer?
- Dot(.)
- Pointer (&)
- Pointer (*)
- Arrow (->)
- Not(~)
Which SQL command comes under data definition language?
- Select
- Drop
- Grant
- Revoke
- Update
The break statement causes an exit
- from the innermost loop or switch
- only from the innermost switch
- only from the innermost loop
- from the program
- from the outermost loop
Deriving a class from another derived class is called
- single inheritance
- multilevel inheritance
- polymorphism
- message passing
- multiple inheritance
Which operator causes a sequence of operations to be performed?
- Comma operator ( , )
- Dot operator( . )
- Cast operator
- Address of operator (&)
- Pointer operator( * )
Which loop executes a sequence of statements multiple times and abbreviates the code that manages the loop variable?
- Do...while loop
- For loop
- While loop
- Nested loop
- If statement
In which data integrity can rows used by other records not be deleted?
- User-defined integrity
- Entity integrity
- Domain integrity
- Referential integrity
- Unique integrity
Which join operation returns row when there is a match in both tables?
- Full join
- Left join
- Cartesian join
- Inner join
- Self join
‘AS’ clause is used in SQL for
- projection operation
- join operation
- rename operation
- selection operation
- delete operation
The expression: int *(*a)[5] means that
- a is pointer to integer
- a is pointer to an array of pointers to integer
- a is pointer to function which returns integer
- a is a pointer to array of size 5
- an array of pointer to function returning pointer to function returning pointer to integer.
Which SQL datatype has maximum length of 4000 characters with variable length unicode?
- The data type char
- The data type nvarchar
- The data type varchar
- The data type varbinary
- The data type nchar
Which SQL logical operator is used to search the presence of a row in a specified table that meets certain criteria?
- Exists operator
- Unique operator
- All operator
- Any operator
- In operator
For (x=4,y=3; x && x!=y; x--)y++;
cout<< “x = %d“<< x << “y = %d “<< y; returns
- x = 0 y = 7
- x = %d0 y = %d 7
- There is an error in the given code.
- x = 1 y = 5
- x = 6 y = 3
In C++, redefining the entire element is called
- shadowing
- function overriding
- function overloading
- function definition
- operator overloading
Which preprocessor directives allows to include or discard part of the code of a program?
- Line control
- Pragma directive
- Macro definitions
- Conditional inclusions
- Error directive
In _____, each node (file server, workstations and peripherals) is connected directly to a central network hub, switch or concentrator.
- star topology
- tree topology
- ring topology
- mesh topology
- bus topology
Which protocol is used for e-mail messages on the internet?
- POP3
- IRC
- IMAP
- FTP
- HTTP
Data link layer and physical layer use
- DNS protocol
- TCP protocol
- ethernet protocol
- SPX protocol
- IP protocol
DHCP is a protocol which automatically assigns internet addresses to computers and users. DHCP stands for
- Dynamic Host Connection Protocol
- Dynamic Host Configuration Protocol
- Distributed Host Configuration Protocol
- Domain Host Configuration Protocol
- Domain Host Connection Protocol
Give an advantage of star topology.
- Failure of one node or link doesn't affect the rest of network.
- Cable length required for this topology is the least compared to other networks.
- Each segment is provided with dedicated point to point wiring to the central hub.
- Expansion and modification in topology can be done without disrupting other nodes.
- Each computer has equal access to resources.
Which of the following is a disadvantage of ring topology?
- Network is highly dependent on the wire which connects different components.
- It is difficult to detect and troubleshoot fault at individual station.
- Performance as well as the number of nodes which can be added in such topology is dependent on the capacity of central device.
- There are high chances of redundancy in many of the network connections.
- Scalability of the network depends on the type of cable used.
Interception of communications by an unauthorised party is called
- denial of service
- spoofing
- phishing
- eavesdropping
- virus
Which level of abstraction describes what data is actually stored in the database?
- Logical view
- Only view
- Conceptual view
- Physical view
- Abstract view
In network security, a logic bomb is
- an undocumented way of gaining access to a system that is built into the system
- a program or subsection of a program designed with malevolent intent
- a program or code fragment that hides inside a program and performs a disguised function
- a self contained and independent program that is usually designed to propagate or spawn itself on infected systems and to seek other systems via available networks
- anything that can disrupt the operation, functioning, integrity or availability of a network or system
___________ uses the concept of a mathematical relation as its basic building block and has its theoretical basis in set theory and first order predicate logic.
- Network model
- Hierarchical model
- Object oriented model
- Relational model
- Object relational model