1. Which of the following is an example of a non-relational DBMS?
A. PostgreSQL
B. SQLite
C. MongoDB
D. Oracle
Answer: C) MongoDB
Rationale: MongoDB is a non-relational (NoSQL) DBMS, which stores data in a flexible,
document-based format.
2. What is the purpose of a database schema?
A. To store data physically
B. To define the structure of the database
C. To ensure referential integrity
D. To store security credentials
Answer: B) To define the structure of the database
Rationale: A schema defines the structure of a database, including tables, columns, and
relationships.
3. Which of the following is NOT a type of DBMS?
,A. Hierarchical
B. Relational
C. Object-oriented
D. Network
Answer: D) Network
Rationale: The common DBMS types include hierarchical, relational, and object-oriented.
"Network" refers to a network model, not a DBMS type.
4. Which of the following ensures that no two rows in a table have the same value in a specified
column?
A. Foreign key
B. Unique key
C. Primary key
D. Composite key
Answer: B) Unique key
Rationale: A unique key ensures that no two rows have the same value in the specified column.
5. What is referential integrity?
A. Ensuring data consistency between tables
B. Enforcing primary key uniqueness
C. Preventing duplication of records
, D. Normalizing data to reduce redundancy
Answer: A) Ensuring data consistency between tables
Rationale: Referential integrity ensures that foreign keys correctly reference primary keys in
related tables.
6. Which of the following is NOT an advantage of normalization?
A. Reduces redundancy
B. Increases data integrity
C. Makes the database more complex
D. Improves query performance
Answer: C) Makes the database more complex
Rationale: Normalization reduces redundancy, improves integrity, but may make the database
more complex with multiple tables.
7. What is an index in a database?
A. A data structure that improves query performance
B. A field used to uniquely identify records
C. A type of foreign key
D. A method for sorting data
Answer: A) A data structure that improves query performance
A. PostgreSQL
B. SQLite
C. MongoDB
D. Oracle
Answer: C) MongoDB
Rationale: MongoDB is a non-relational (NoSQL) DBMS, which stores data in a flexible,
document-based format.
2. What is the purpose of a database schema?
A. To store data physically
B. To define the structure of the database
C. To ensure referential integrity
D. To store security credentials
Answer: B) To define the structure of the database
Rationale: A schema defines the structure of a database, including tables, columns, and
relationships.
3. Which of the following is NOT a type of DBMS?
,A. Hierarchical
B. Relational
C. Object-oriented
D. Network
Answer: D) Network
Rationale: The common DBMS types include hierarchical, relational, and object-oriented.
"Network" refers to a network model, not a DBMS type.
4. Which of the following ensures that no two rows in a table have the same value in a specified
column?
A. Foreign key
B. Unique key
C. Primary key
D. Composite key
Answer: B) Unique key
Rationale: A unique key ensures that no two rows have the same value in the specified column.
5. What is referential integrity?
A. Ensuring data consistency between tables
B. Enforcing primary key uniqueness
C. Preventing duplication of records
, D. Normalizing data to reduce redundancy
Answer: A) Ensuring data consistency between tables
Rationale: Referential integrity ensures that foreign keys correctly reference primary keys in
related tables.
6. Which of the following is NOT an advantage of normalization?
A. Reduces redundancy
B. Increases data integrity
C. Makes the database more complex
D. Improves query performance
Answer: C) Makes the database more complex
Rationale: Normalization reduces redundancy, improves integrity, but may make the database
more complex with multiple tables.
7. What is an index in a database?
A. A data structure that improves query performance
B. A field used to uniquely identify records
C. A type of foreign key
D. A method for sorting data
Answer: A) A data structure that improves query performance