Computer Operators 2026

1. DBMS stands for:
A. Data Backup Management System
B. Database Management System
C. Database Monitoring System
D. Data Management Service
Answer: B
2. A database is:
A. Collection of programs
B. Collection of related data
C. Collection of hardware
D. Collection of networks
Answer: B
3. Which is NOT a DBMS?
A. MySQL
B. Oracle
C. PostgreSQL
D. HTML
Answer: D
4. The main purpose of DBMS is to:
A. Create hardware
B. Manage and organise data
C. Design networks
D. Compile programs
Answer: B
5. Which model represents data in tables?
A. Hierarchical
B. Network
C. Relational
D. Object-oriented
Answer: C
6. In a relational database, a table is also called:
A. Tuple
B. Relation
C. Attribute
D. Domain
Answer: B
7. A row in a relational table is called:
A. Attribute
B. Tuple
C. Domain
D. Field
Answer: B
8. A column in a relational table is called:
A. Tuple
B. Record
C. Attribute
D. Relation
Answer: C
9. Which identifies each record uniquely?
A. Foreign Key
B. Primary Key
C. Alternate Key
D. Composite Key
Answer: B
10. A primary key can contain:
A. Duplicate values
B. NULL values
C. Unique values only
D. Only text
Answer: C
11. A foreign key is used to:
A. Encrypt data
B. Establish relationship between tables
C. Delete tables
D. Create users
Answer: B
12. Which constraint ensures uniqueness?
A. CHECK
B. DEFAULT
C. UNIQUE
D. NULL
Answer: C
13. Which constraint prevents NULL values?
A. NOT NULL
B. UNIQUE
C. DEFAULT
D. CHECK
Answer: A
14. Which constraint validates a condition?
A. CHECK
B. PRIMARY KEY
C. FOREIGN KEY
D. DEFAULT
Answer: A
15. Which constraint provides a value automatically?
A. CHECK
B. DEFAULT
C. UNIQUE
D. NULL
Answer: B
16. DBMS provides:
A. Data security
B. Data integrity
C. Concurrency control
D. All of the above
Answer: D
17. Data redundancy means:
A. Data encryption
B. Unnecessary duplication of data
C. Data deletion
D. Data validation
Answer: B
18. DBMS helps reduce:
A. Data redundancy
B. Data security
C. Data availability
D. Data integrity
Answer: A
19. Metadata means:
A. Data about data
B. Deleted data
C. Encrypted data
D. Duplicate data
Answer: A
20. Data dictionary contains:
A. Metadata
B. Only passwords
C. Only tables
D. Only records
Answer: A
21. The logical structure of a database is called:
A. Schema
B. Instance
C. Query
D. View
Answer: A
22. The actual data stored at a particular time is called:
A. Schema
B. Instance
C. Domain
D. Relation
Answer: B
23. Which is a database administrator's responsibility?
A. Backup and recovery
B. Security management
C. Performance tuning
D. All of the above
Answer: D
24. DBA stands for:
A. Database Business Administrator
B. Database Administrator
C. Data Backup Administrator
D. Database Application
Answer: B
25. Which is an advantage of DBMS?
A. Increased redundancy
B. Improved data security
C. Increased inconsistency
D. Reduced data sharing
Answer: B
26–50: SQL
26. SQL stands for:
A. Structured Query Language
B. Simple Query Language
C. System Query Language
D. Structured Question Language
Answer: A
27. Which command retrieves data?
A. INSERT
B. SELECT
C. UPDATE
D. DELETE
Answer: B
28. Which is a DDL command?
A. SELECT
B. INSERT
C. CREATE
D. UPDATE
Answer: C
29. Which is a DML command?
A. CREATE
B. ALTER
C. INSERT
D. DROP
Answer: C
30. Which is a DCL command?
A. GRANT
B. SELECT
C. UPDATE
D. CREATE
Answer: A
31. Which is a TCL command?
A. COMMIT
B. CREATE
C. SELECT
D. ALTER
Answer: A
32. Which command creates a table?
A. MAKE TABLE
B. CREATE TABLE
C. NEW TABLE
D. ADD TABLE
Answer: B
33. Which command removes a table permanently?
A. DELETE
B. REMOVE
C. DROP
D. CLEAR
Answer: C
34. Which command modifies table structure?
A. UPDATE
B. ALTER
C. MODIFY DATA
D. CHANGE
Answer: B
35. Which command removes all rows but keeps table structure?
A. DROP
B. DELETE
C. TRUNCATE
D. REMOVE
Answer: C
36. Which command is used to modify existing records?
A. UPDATE
B. ALTER
C. MODIFY TABLE
D. CHANGE
Answer: A
37. Which command adds a new record?
A. ADD
B. INSERT
C. APPEND TABLE
D. CREATE
Answer: B
38. Which clause filters records?
A. ORDER BY
B. WHERE
C. GROUP BY
D. HAVING
Answer: B
39. Which clause sorts query results?
A. SORT BY
B. ORDER BY
C. GROUP BY
D. ARRANGE BY
Answer: B
40. Default sorting order of ORDER BY is:
A. DESC
B. ASC
C. RANDOM
D. NONE
Answer: B
41. Which keyword removes duplicate results?
A. UNIQUE
B. DISTINCT
C. DIFFERENT
D. REMOVE
Answer: B
42. Which function counts rows?
A. SUM()
B. COUNT()
C. TOTAL()
D. NUMBER()
Answer: B
43. Which function calculates average?
A. AVG()
B. MEAN()
C. AVERAGE()
D. MID()
Answer: A
44. Which function returns maximum value?
A. HIGH()
B. MAX()
C. TOP()
D. UPPER()
Answer: B
45. Which function returns minimum value?
A. LOW()
B. MIN()
C. LOWER()
D. BOTTOM()
Answer: B
46. Which operator is used for pattern matching?
A. IN
B. LIKE
C. MATCH
D. BETWEEN
Answer: B
47. SQL wildcard % represents:
A. Exactly one character
B. Zero or more characters
C. Only numbers
D. A space
Answer: B
48. SQL wildcard _ represents:
A. Zero characters
B. One character
C. Multiple characters
D. Numbers only
Answer: B
49. Which operator checks a range?
A. IN
B. BETWEEN
C. RANGE
D. WITHIN
Answer: B
50. Which operator checks whether a value belongs to a list?
A. IN
B. BETWEEN
C. LIKE
D. EXISTS
Answer: A
51–75: Normalisation, Keys & Relationships
51. Normalization is primarily used to:
A. Increase redundancy
B. Reduce redundancy
C. Increase duplication
D. Delete data
Answer: B
52. First Normal Form (1NF) requires:
A. No foreign keys
B. Atomic values
C. No primary key
D. No NULL values
Answer: B
53. 2NF is based on:
A. 1NF
B. 3NF
C. BCNF
D. 4NF
Answer: A
54. 2NF eliminates:
A. Transitive dependency
B. Partial dependency
C. Multivalued dependency
D. Functional dependency
Answer: B
55. 3NF eliminates:
A. Partial dependency
B. Transitive dependency
C. Multivalued dependency
D. Primary key
Answer: B
56. BCNF stands for:
A. Boyce-Codd Normal Form
B. Basic-Codd Normal Form
C. Boyce-Codd Network Form
D. Binary-Codd Normal Form
Answer: A
57. A candidate key is:
A. Any foreign key
B. Minimal superkey
C. Duplicate key
D. NULL key
Answer: B
58. A superkey:
A. Uniquely identifies tuples
B. Must always be minimal
C. Cannot contain multiple attributes
D. Is always a foreign key
Answer: A
59. A candidate key selected to identify records is called:
A. Foreign key
B. Primary key
C. Alternate key
D. Secondary key
Answer: B
60. Candidate keys not selected as primary key are:
A. Foreign keys
B. Alternate keys
C. Super keys
D. Composite keys
Answer: B
61. A key consisting of multiple attributes is called:
A. Simple key
B. Composite key
C. Foreign key
D. Alternate key
Answer: B
62. A relationship between two tables is commonly established using:
A. Primary and Foreign keys
B. CHECK constraints
C. Views
D. Indexes only
Answer: A
63. One student can enrol in many courses and one course can have many students. This is:
A. 1:1
B. 1:M
C. M:N
D. 0:1
Answer: C
64. One department has many employees. This is:
A. 1:1
B. 1:M
C. M:N
D. M:1 only
Answer: B
65. One person has one passport is an example of:
A. 1:1
B. 1:M
C. M:N
D. M:M
Answer: A
66. ER model stands for:
A. Entity Relationship Model
B. Electronic Record Model
C. Entity Record Model
D. Extended Relation Model
Answer: A
67. In an ER diagram, an entity is commonly represented by:
A. Rectangle
B. Circle
C. Diamond
D. Triangle
Answer: A
68. An attribute is commonly represented by:
A. Rectangle
B. Oval
C. Diamond
D. Line
Answer: B
69. Relationship is commonly represented by:
A. Rectangle
B. Oval
C. Diamond
D. Circle
Answer: C
70. An entity that depends on another entity for identification is:
A. Strong entity
B. Weak entity
C. Super entity
D. Parent entity
Answer: B
71. A weak entity is generally represented by:
A. Double rectangle
B. Single rectangle
C. Oval
D. Triangle
Answer: A
72. Cardinality describes:
A. Data type
B. Number of entities participating in a relationship
C. Database size
D. Storage capacity
Answer: B
73. Which is NOT a normal form?
A. 1NF
B. 2NF
C. 3NF
D. 7NF
Answer: D
74. Denormalization is generally used to:
A. Reduce query performance
B. Improve read performance in some cases
C. Remove all redundancy
D. Eliminate tables
Answer: B
75. Functional dependency is represented as:
A. A → B
B. A = B
C. A + B
D. A × B
Answer: A
76–100: Transactions, Indexing, Security & Advanced DBMS
76. A transaction is:
A. A single database table
B. A logical unit of database work
C. A database user
D. An index
Answer: B
77. ACID stands for:
A. Atomicity, Consistency, Isolation, Durability
B. Accuracy, Consistency, Integrity, Data
C. Atomicity, Control, Integrity, Durability
D. Access, Control, Isolation, Data
Answer: A
78. Atomicity means:
A. Transaction is partially completed
B. All operations occur or none occur
C. Data is always encrypted
D. Multiple users can access data
Answer: B
79. Consistency ensures:
A. Database moves from one valid state to another
B. Data is duplicated
C. Transaction is always fast
D. Data is deleted
Answer: A
80. Isolation means:
A. Transactions interfere with each other
B. Concurrent transactions behave appropriately as if isolated
C. Database is disconnected
D. Users cannot access data
Answer: B
81. Durability means:
A. Committed changes survive failures
B. Data is temporary
C. Data is deleted after transaction
D. Data is never backed up
Answer: A
82. Which command permanently saves a transaction?
A. SAVE
B. COMMIT
C. STORE
D. APPLY
Answer: B
83. Which command undoes uncommitted changes?
A. UNDO
B. ROLLBACK
C. CANCEL
D. RESET
Answer: B
84. A deadlock occurs when:
A. Database has no users
B. Transactions wait indefinitely for each other
C. A table is deleted
D. Query executes quickly
Answer: B
85. Which is used to improve data retrieval speed?
A. Index
B. Trigger
C. View
D. Constraint
Answer: A
86. An index is primarily used for:
A. Faster data retrieval
B. Data encryption
C. Data deletion
D. User authentication
Answer: A
87. A clustered index determines:
A. Physical/logical ordering of table data in supported DBMS implementations
B. User password
C. Database name
D. Foreign key
Answer: A
88. A view is:
A. Physical copy of a database
B. Virtual table based on a query
C. Backup file
D. Index
Answer: B
89. Which command creates a view?
A. CREATE VIEW
B. MAKE VIEW
C. NEW VIEW
D. BUILD VIEW
Answer: A
90. A stored procedure is:
A. A stored executable set of SQL statements
B. A table
C. A key
D. A database backup
Answer: A
91. A trigger is:
A. Automatically executed in response to specified database events
B. A backup mechanism only
C. A type of key
D. A data type
Answer: A
92. Which is commonly used to prevent SQL injection?
A. Parameterized queries
B. More indexes
C. More tables
D. DELETE command
Answer: A
93. SQL injection is:
A. Database backup technique
B. Attack through malicious SQL input
C. Normalization technique
D. Indexing technique
Answer: B
94. Which command gives privileges to a user?
A. GRANT
B. ALLOW
C. PERMIT
D. AUTHORIZE
Answer: A
95. Which command removes privileges?
A. DELETE
B. REVOKE
C. REMOVE
D. DENY
Answer: B
96. Database backup is primarily used for:
A. Recovery
B. Normalization
C. Indexing
D. Query sorting
Answer: A
97. Database recovery is required mainly after:
A. System failure
B. Successful query
C. Table creation
D. User login
Answer: A
98. OLTP stands for:
A. Online Transaction Processing
B. Online Table Processing
C. Offline Transaction Processing
D. Online Transfer Processing
Answer: A
99. OLAP stands for:
A. Online Analytical Processing
B. Online Application Processing
C. Offline Analytical Processing
D. Online Access Protocol
Answer: A
100. Which database architecture separates user interface, application logic and database?
A. 1-tier
B. 2-tier
C. 3-tier
D. 4-tier
Answer: C

1. Which type of software is an Antivirus program?
A) System Software
B) Utility Software
C) Application Software
D) Operating System
2. Which shortcut key is used to insert a new slide in MS-PowerPoint?
A) Ctrl + N
B) Ctrl + M
C) Ctrl + S
D) Ctrl + Shift + N
3. Which protocol is used to receive or download emails from a mail server to a local client?
A) SMTP
B) POP3
C) FTP
D) HTTP
4. What is the intersection of a row and a column in a spreadsheet called?
A) Data
B) Formula
C) Cell
D) Field
5. Which of the following is a volatile storage device?
A) Hard Disk Drive (HDD)
B) Solid State Drive (SSD)
C) Cache Memory
D) Compact Disc (CD)
लोक सेवा आयोग (Lok Sewa Aayog) को नयाँ पाठ्यक्रममा आधारित Computer Operator को सेट-४ (Set-4) MCQ प्रश्नहरू! 📚✨
आफ्नो तयारीलाई निरन्तरता दिनुहोस् र यी प्रश्नहरूको सहि उत्तर कमेन्टमा लेख्नुहोस्। आगामी परीक्षाका लागि शुभकामना! 👇

1. Which device is used to connect two different types of networks, such as a LAN and a WAN?
A) Hub
B) Switch
C) Router
D) Repeater
2. Which function key is used to check spelling and grammar in MS-Word?
A) F2
B) F7
C) F5
D) F12
3. Which of the following is a shortcut key to create a new chart from the selected data in MS-Excel?
A) F1
B) F11
C) F9
D) F4
4. What is the maximum length of a file name in FAT32 file system?
A) 8 characters
B) 128 characters
C) 255 characters
D) No limit
5. Which SQL command is used to retrieve data from a database?
A) UPDATE
B) SELECT
C) INSERT
D) DELETE
लोक सेवा आयोग (Lok Sewa Aayog) को नयाँ पाठ्यक्रममा आधारित Computer Operator को सेट-३ (Set-3) MCQ प्रश्नहरू! 📚✨
नियमित अभ्यासले सफलता नजिक ल्याउँछ। आफ्ना साथीहरूलाई ट्याग गर्नुहोस् र सहि उत्तर कमेन्ट गर्नुहोस्! 👇

1. Which memory is volatile in nature?
A) ROM
B) RAM
C) Hard Disk
D) EEPROM
2. What is the extension of a template file in MS-Word (2007 and later)?
A) .docx
B) .dotx
C) .xlsx
D) .pptx
3. Which network topology requires a central controller or hub?
A) Mesh
B) Ring
C) Star
D) Bus
4. Which of the following is a Relational Database Management System (RDBMS)?
A) MS-Access
B) MongoDB
C) Redis
D) Cassandra
5. What is the default port number for HTTP (Hypertext Transfer Protocol)?
A) 21
B) 25
C) 80
D) 443
लोक सेवा आयोग (Lok Sewa Aayog) को नयाँ पाठ्यक्रममा आधारित Computer Operator को सेट-२ (Set-2) MCQ प्रश्नहरू! 📚✨
तयारीलाई अझै उत्कृष्ट बनाउनुहोस् र सहि उत्तर कमेन्ट गर्नुहोस्। साथीहरूसँग सेयर गर्न नभुल्नुहोला! 👇

5. In MS-Excel, formulas always begin with which symbol?
A) #
B) @
C) =
D) %

4. Which shortcut key is used to paste copied text or file in Windows?
A) Ctrl + C
B) Ctrl + V
C) Ctrl + X
D) Ctrl + P

3. What does 'HTTP' stand for in web addresses?
A) HyperText Transfer Protocol
B) HyperText Transmission Process
C) HyperText Transfer Program
D) Hyperlink Transfer Protocol

2. Which of the following is NOT an operating system?
A) Linux
B) Windows
C) Oracle
D) macOS

1. Which of the following is considered as the 'Brain' of the computer?
A) Hard Disk
B) Central Processing Unit (CPU)
C) Random Access Memory (RAM)
D) Control Unit