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1. What is the main purpose of a database management system (DBMS)?

A) Drawing graphs
B) Compiling code
C) Storing and managing data
D) Editing images

ANSWER= C) Storing and managing data

2. In manual record-keeping, which of the following is a major disadvantage?

A) Costly software
B) Inconsistent handwriting
C) Redundancy and inaccuracy
D) Online data sharing

ANSWER= C) Redundancy and inaccuracy

3. Which component of a database is used to store records about events such as student attendance?

A) Entity
B) Relation
C) Schema
D) Constraint

ANSWER= B) Relation

4. What does ‘data redundancy’ mean?

A) Missing values
B) Use of online databases
C) Repetition of the same data in multiple files
D) Use of digital files

ANSWER= C) Repetition of the same data in multiple files

5. Which of the following is NOT a limitation of the file system?

A) Data isolation
B) Data independence
C) Data consistency
D) Controlled data sharing

ANSWER= C) Data consistency

6. Which attribute connects STUDENT and GUARDIAN tables in DBMS?

A) RollNumber
B) GName
C) GUID
D) GPhone

ANSWER= C) GUID

7. Which of these is a benefit of DBMS over a file system?

A) Redundancy increases
B) Harder to access
C) Better data integrity
D) Data stored manually

ANSWER= C) Better data integrity

8. What type of value is considered ‘atomic’?

A) A null value
B) A unique identifier
C) An indivisible value
D) A composite key

ANSWER= C) An indivisible value

9. Which of these is a data constraint?

A) Variable naming
B) Data formats
C) NOT NULL
D) Query syntax

ANSWER= C) NOT NULL

10. A schema defines:

A) The table rows
B) The data inside a table
C) The structure of a database
D) The speed of transactions

ANSWER= C) The structure of a database

11. What is meta-data in a database system?

A) Summary table
B) Data about the data
C) A type of primary key
D) Redundant data

ANSWER= B) Data about the data

12. Which one is NOT a component of a relational database model?

A) Attribute
B) Table
C) Diagram
D) Tuple

ANSWER= C) Diagram

13. Which operation is not considered part of data manipulation?

A) Insert
B) Update
C) Schema creation
D) Delete

ANSWER= C) Schema creation

14. What does the term ‘database instance’ refer to?

A) The original schema
B) A table definition
C) A snapshot of the data at a particular time
D) A type of user account

ANSWER= C) A snapshot of the data at a particular time

15. Which of the following statements is true for relational databases?

A) Tables are isolated
B) Tuples must be unique
C) Attributes may have different domains in one table
D) Rows are stored in hierarchical order

ANSWER= B) Tuples must be unique

16. Which key refers to a primary key from another table?

A) Alternate key
B) Candidate key
C) Foreign key
D) Composite key

ANSWER= C) Foreign key

17. GUID in the GUARDIAN table is an example of:

A) Foreign key
B) Candidate key
C) Alternate key
D) Composite key

ANSWER= B) Candidate key

18. Which of the following is NOT stored in the meta-data (catalog)?

A) Table structure
B) Constraints
C) Data records
D) Data types

ANSWER= C) Data records

19. A tuple is:

A) A unique column name
B) A data file
C) A row in a table
D) A type of schema

ANSWER= C) A row in a table

20. In a relation, the number of columns is known as:

A) Tuple
B) Degree
C) Cardinality
D) Attribute

ANSWER= B) Degree

21. What does the term ‘cardinality’ refer to in databases?

A) Number of columns
B) Number of unique values
C) Number of rows
D) Type of key used

ANSWER= C) Number of rows

22. What type of primary key does the ATTENDANCE table use?

A) Single attribute
B) Alternate key
C) Composite key
D) Unique constraint

ANSWER= C) Composite key

23. Which combination is used as a composite primary key in ATTENDANCE?

A) RollNumber and GName
B) RollNumber and AttendanceDate
C) RollNumber and SName
D) GUID and GName

ANSWER= B) RollNumber and AttendanceDate

24. A primary key must be:

A) NULL
B) Repetitive
C) Unique and NOT NULL
D) From a foreign table

ANSWER= C) Unique and NOT NULL

25. A student record showing multiple preferences in one field violates:

A) Domain integrity
B) Entity integrity
C) Atomicity
D) Cardinality

ANSWER= C) Atomicity

26. What happens if a file’s structure is changed in a file system?

A) Nothing changes
B) The application automatically updates
C) Old applications may not work correctly
D) File size reduces

ANSWER= C) Old applications may not work correctly

27. The ability to limit access to data in DBMS is called:

A) Querying
B) Role sharing
C) Controlled data sharing
D) Tuple isolation

ANSWER= C) Controlled data sharing

28. Which DBMS feature allows data changes over time?

A) Static schema
B) Database instance
C) Meta-data
D) Query cache

ANSWER= B) Database instance

29. In a well-designed relational database, redundancy is minimized by:

A) Adding repeated columns
B) Storing all data in one table
C) Separating related data into different tables
D) Copying data across tables

ANSWER= C) Separating related data into different tables

30. What is the purpose of a query in DBMS?

A) Design the database
B) Delete the database
C) Retrieve or manipulate data
D) Backup records

ANSWER= C) Retrieve or manipulate data

31. A database engine is:

A) A type of hardware
B) Used for reporting
C) Underlying component that processes queries
D) A manual entry tool

ANSWER= C) Underlying component that processes queries

32. In relational databases, what does the term “degree” refer to?

A) Number of rows
B) Number of keys
C) Number of columns
D) Number of schemas

ANSWER= C) Number of columns

33. NULL is used to represent:

A) Duplicate values
B) Unknown or inapplicable data
C) Redundant values
D) Negative numbers

ANSWER= B) Unknown or inapplicable data

34. The domain of an attribute defines:

A) The speed of access
B) The formatting style of rows
C) The set of valid values for that attribute
D) The number of foreign keys in a table

ANSWER= C) The set of valid values for that attribute

35. Which of the following fields is NOT typically stored in a business-oriented database?

A) Customer details
B) Employee records
C) Product pricing
D) Color scheme of the website

ANSWER= D) Color scheme of the website

36. A set of fields that uniquely identifies a row is called a:

A) Schema
B) Query
C) Key
D) Constraint

ANSWER= C) Key

37. In a relational database, a foreign key is used to:

A) Automatically generate queries
B) Identify duplicate records
C) Link records in two related tables
D) Enforce data encryption

ANSWER= C) Link records in two related tables

38. Which of the following is considered a data manipulation operation?

A) Designing a schema
B) Inserting a new record
C) Creating a table
D) Enforcing constraints

ANSWER= B) Inserting a new record

39. Which of the following is NOT a data manipulation operation?

A) Insert
B) Delete
C) Update
D) Creating a table

ANSWER= D) Creating a table

40. What is the function of the NOT NULL constraint in a database?

A) It allows multiple values
B) Ensures the attribute must always have a value
C) Prevents duplicate rows
D) Makes a key composite

ANSWER= B) Ensures the attribute must always have a value

41. Which of the following supports logical organization of data?

A) File System
B) Operating System
C) Database Schema
D) Data Dictionary

ANSWER= C) Database Schema

42. Which DBMS type is listed in the textbook as open-source?

A) Oracle
B) SQL Server
C) PostgreSQL
D) MS Access

ANSWER= C) PostgreSQL

43. Which technique is used in DBMS to avoid data inconsistency?

A) File backups
B) Repetitive data entry
C) Data normalization and schema design
D) Ignoring updates

ANSWER= C) Data normalization and schema design

44. Relationships between tables in a DBMS are created using:

A) Primary Keys
B) Constraints
C) Foreign Keys
D) Data files

ANSWER= C) Foreign Keys

45. Redundant data can lead to:

A) Faster performance
B) Data inconsistency
C) Better backups
D) Easier file access

ANSWER= B) Data inconsistency

46. Which rule applies to attributes in a relational table?

A) They must be composite
B) They must all have NULL values
C) They must have unique names
D) They must be stored in alphabetical order

ANSWER= C) They must have unique names

47. To uniquely identify each student’s attendance on a particular day, DBMS uses:

A) Multiple tables
B) Student name
C) Composite primary key
D) Guardian name

ANSWER= C) Composite primary key

48. Which of the following lets you specify rules on a column?

A) Table view
B) Meta-data
C) Constraint
D) Query

ANSWER= C) Constraint

49. A student record (row) in the STUDENT table is an example of:

A) Attribute
B) Tuple
C) Schema
D) Key

ANSWER= B) Tuple

50. Which feature ensures correctness and reliability of database content?

A) Tuples
B) SQL
C) Constraints
D) Domains

ANSWER= C) Constraints

51. Assertion (A): A database schema defines the structure of a database. Reason (R): Schema stores actual data records.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is true, but R is false
D) A is false, but R is true

ANSWER= C) A is true, but R is false

52. Assertion (A): In a relational database, each attribute must have a unique name. Reason (R): Unique attribute names help avoid ambiguity during data manipulation.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is true, but R is false
D) A is false, but R is true

ANSWER= A) Both A and R are true, and R is the correct explanation of A

53. Assertion (A): A primary key must be unique and NOT NULL. Reason (R): A primary key is used to link data between unrelated databases.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is true, but R is false
D) A is false, but R is true

ANSWER= C) A is true, but R is false

54. Assertion (A): A foreign key is an attribute that helps relate two tables. Reason (R): A foreign key always references the primary key of another table.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is true, but R is false
D) A is false, but R is true

ANSWER= A) Both A and R are true, and R is the correct explanation of A

55. Assertion (A): A composite primary key is made using more than one attribute. Reason (R): Composite keys are used when no single attribute can uniquely identify records.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is true, but R is false
D) A is false, but R is true

ANSWER= A) Both A and R are true, and R is the correct explanation of A

56. Assertion (A): File systems provide strong data consistency across multiple files. Reason (R): File systems automatically update redundant data when a change is made.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is true, but R is false
D) A is false, but R is false

ANSWER= D) A is false, but R is false

57. Assertion (A): Constraints in DBMS ensure data integrity. Reason (R): Constraints allow only valid data to be stored in the database.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is true, but R is false
D) A is false, but R is true

ANSWER= A) Both A and R are true, and R is the correct explanation of A

58. Assertion (A): A field storing multiple values in one cell improves query speed. Reason (R): Relational databases allow non-atomic values for flexibility.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is true, but R is false
D) A is false, but R is false

ANSWER= D) A is false, but R is false

59. Assertion (A): The domain of an attribute defines the allowed values for that attribute. Reason (R): Domain helps ensure that data stored in a column is valid.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is true, but R is false
D) A is false, but R is true

ANSWER= A) Both A and R are true, and R is the correct explanation of A

60. Assertion (A): All candidate keys are automatically selected as primary keys. Reason (R): Candidate keys are eligible to become primary keys.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is false, but R is true
D) A is true, but R is false

ANSWER= C) A is false, but R is true

61. Assertion (A): Metadata contains information about database structure. Reason (R): Metadata helps the DBMS validate queries and enforce constraints.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is false, but R is true
D) A is true, but R is false

ANSWER= A) Both A and R are true, and R is the correct explanation of A

62. Assertion (A): Cardinality of a relation refers to the number of columns in the table. Reason (R): Columns represent the attributes of a relation.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is false, but R is true
D) A is true, but R is false

ANSWER= C) A is false, but R is true

63. Assertion (A): Normalization removes data redundancy. Reason (R): Redundant data may lead to data inconsistency.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is true, but R is false
D) A is false, but R is true

ANSWER= A) Both A and R are true, and R is the correct explanation of A

64. Assertion (A): The NOT NULL constraint prevents NULL entries in a column. Reason (R): It ensures that every row has a value in that column.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is true, but R is false
D) A is false, but R is true

ANSWER= A) Both A and R are true, and R is the correct explanation of A

65. Assertion (A): DBMS allows multiple users to interact with the same data concurrently. Reason (R): DBMS uses controlled data sharing and access permissions.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is true, but R is false
D) A is false, but R is true

ANSWER= A) Both A and R are true, and R is the correct explanation of A

66. Assertion (A): The structure of a table can be modified using data manipulation queries. Reason (R): Commands like ALTER and CREATE are part of data manipulation language.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is false, but R is true
D) A is true, but R is false

ANSWER= C) A is false, but R is true

67. Assertion (A): DBMS helps reduce data inconsistency by storing data in one central location. Reason (R): Centralized control and constraints ensure that all data updates remain consistent.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is true, but R is false
D) A is false, but R is true

ANSWER= A) Both A and R are true, and R is the correct explanation of A

68. Assertion (A): A database instance can change over time. Reason (R): An instance represents the current snapshot of the data.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is true, but R is false
D) A is false, but R is true

ANSWER= A) Both A and R are true, and R is the correct explanation of A

69. Assertion (A): SQL allows users to retrieve, insert, and update data. Reason (R): SQL is the standard language for managing relational databases.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is true, but R is false
D) A is false, but R is true

ANSWER= A) Both A and R are true, and R is the correct explanation of A

70. Assertion (A): Degree of a relation is defined by the number of attributes it contains. Reason (R): Attributes define the structure of each record in a relation.

A) Both A and R are true, and R is the correct explanation of A
B) Both A and R are true, but R is not the correct explanation of A
C) A is false, but R is true
D) A is true, but R is false

ANSWER= A) Both A and R are true, and R is the correct explanation of A