Q. What is the main goal of the Third Normal Form (3NF)?
A.To eliminate transitive dependencies
B.To ensure all attributes are dependent on the primary key
C.To remove duplicate rows
D.To create a unique identifier for each record
Solution
The main goal of 3NF is to eliminate transitive dependencies, ensuring that non-key attributes are only dependent on the primary key.
Correct Answer: A — To eliminate transitive dependencies
Q. What is the main purpose of an ER model?
A.To define SQL queries
B.To visualize database structure
C.To manage transactions
D.To optimize indexing
Solution
The main purpose of an ER model is to visualize the structure of a database, including entities, attributes, and relationships.
Correct Answer: B — To visualize database structure
Q. What is the main purpose of concurrency control in a DBMS?
A.To prevent data loss
B.To ensure data consistency
C.To speed up data retrieval
D.To manage user permissions
Solution
The main purpose of concurrency control in a DBMS is to ensure data consistency when multiple transactions are executed simultaneously.
Correct Answer: B — To ensure data consistency
Q. What is the main purpose of data normalization in a data warehouse?
A.To reduce data redundancy
B.To improve query performance
C.To enhance data integrity
D.To simplify data retrieval
Solution
Data normalization aims to reduce data redundancy and improve data integrity, although it is less common in data warehousing compared to operational databases.
Correct Answer: A — To reduce data redundancy
Q. What is the main purpose of indexing in a database?
A.To store data
B.To enforce data integrity
C.To speed up data retrieval
D.To manage transactions
Solution
The main purpose of indexing in a database is to speed up data retrieval operations.
Correct Answer: C — To speed up data retrieval
Q. What is the primary function of OLAP in data warehousing?
A.To perform online transaction processing
B.To support complex queries and data analysis
C.To manage data integrity
D.To facilitate data entry
Solution
OLAP (Online Analytical Processing) is used in data warehousing to support complex queries and data analysis.
Correct Answer: B — To support complex queries and data analysis
Q. What is the primary key in an entity?
A.A unique identifier for each record
B.An attribute that can be null
C.A foreign key from another entity
D.An attribute that is not used in relationships
Solution
The primary key is a unique identifier for each record in an entity.
Correct Answer: A — A unique identifier for each record
Q. What is the primary purpose of a data warehouse?
A.To store operational data
B.To support business intelligence activities
C.To manage transaction processing
D.To perform real-time analytics
Solution
A data warehouse is designed to support business intelligence activities by consolidating data from various sources for analysis.
Correct Answer: B — To support business intelligence activities
Q. What is the primary purpose of normalization in a database?
A.To increase data redundancy
B.To eliminate data anomalies
C.To improve query performance
D.To simplify database design
Solution
Normalization is used to eliminate data anomalies and ensure data integrity by organizing data into related tables.
Correct Answer: B — To eliminate data anomalies
Q. What is the primary purpose of normalization in database design?
A.To increase data redundancy
B.To eliminate data anomalies
C.To improve query performance
D.To simplify database architecture
Solution
Normalization is used to eliminate data anomalies and ensure data integrity by organizing data into related tables.
Correct Answer: B — To eliminate data anomalies
Q. What is the purpose of a data model in database design?
A.To define the physical storage of data
B.To represent data structures and relationships
C.To optimize query performance
D.To enforce data integrity constraints
Solution
A data model represents data structures and relationships, serving as a blueprint for database design.
Correct Answer: B — To represent data structures and relationships
Q. What is the purpose of a database schema?
A.To store data
B.To define the structure of the database
C.To manage user access
D.To optimize queries
Solution
A database schema defines the structure of the database, including tables, fields, relationships, and constraints.
Correct Answer: B — To define the structure of the database
Q. What is the purpose of a foreign key in a relational database?
A.To uniquely identify a record
B.To create a relationship between two tables
C.To enforce data integrity
D.All of the above
Solution
A foreign key serves to create a relationship between two tables and enforce data integrity by ensuring that the value in one table corresponds to a valid record in another.
Correct Answer: D — All of the above
Q. What is the purpose of a primary key in a database table?
A.To uniquely identify each record
B.To link tables together
C.To enforce data types
D.To store large amounts of data
Solution
A primary key is used to uniquely identify each record in a database table.
Correct Answer: A — To uniquely identify each record
Q. What is the purpose of a transaction in a database?
A.To store data permanently
B.To ensure data integrity
C.To create backups
D.To optimize queries
Solution
The purpose of a transaction in a database is to ensure data integrity by grouping a set of operations that must all succeed or fail together.
Correct Answer: B — To ensure data integrity
Q. What is the purpose of a transaction in a DBMS?
A.To store data
B.To ensure data integrity
C.To create indexes
D.To define schemas
Solution
The purpose of a transaction in a DBMS is to ensure data integrity by grouping operations that must all succeed or fail together.
Correct Answer: B — To ensure data integrity
Q. What is the purpose of an associative entity in an ER model?
A.To represent a many-to-many relationship
B.To store attributes of a relationship
C.To simplify complex relationships
D.All of the above
Solution
An associative entity is used to represent a many-to-many relationship and can store attributes of that relationship.
Correct Answer: D — All of the above
Q. What is the purpose of concurrency control in a DBMS?
A.To manage data redundancy
B.To ensure data integrity during simultaneous transactions
C.To optimize query performance
D.To simplify database design
Solution
Concurrency control ensures data integrity when multiple transactions occur simultaneously in a database.
Correct Answer: B — To ensure data integrity during simultaneous transactions
Q. What is the purpose of data normalization in a data warehouse?
A.To reduce data redundancy
B.To improve query performance
C.To enhance data integrity
D.To simplify data retrieval
Solution
Normalization aims to reduce data redundancy and improve data integrity, although data warehouses often use denormalization for performance.
Correct Answer: A — To reduce data redundancy
Q. What is the purpose of ETL in data warehousing?
A.Extract, Transform, Load
B.Evaluate, Test, Launch
C.Execute, Transfer, Log
D.Enhance, Transfer, Load
Solution
ETL stands for Extract, Transform, Load, which is the process of moving data from source systems into a data warehouse.
Correct Answer: A — Extract, Transform, Load
Q. What is the purpose of indexing in a database?
A.To enforce data integrity
B.To speed up data retrieval
C.To normalize data
D.To create relationships between tables
Solution
Indexing is used to speed up data retrieval operations on a database.
Correct Answer: B — To speed up data retrieval
Q. What is the purpose of indexing in a distributed database?
A.To increase data redundancy
B.To speed up data retrieval
C.To ensure data consistency
D.To manage user permissions
Solution
Indexing in a distributed database is used to speed up data retrieval by creating a data structure that allows for faster searches.
Correct Answer: B — To speed up data retrieval
Q. What is the purpose of normalization in a database?
A.To increase redundancy
B.To eliminate data anomalies
C.To improve query performance
D.To simplify database design
Solution
Normalization is a process that organizes data to reduce redundancy and improve data integrity by eliminating data anomalies.
Correct Answer: B — To eliminate data anomalies
Q. What is the purpose of normalization in database design?
A.To increase redundancy
B.To eliminate data anomalies
C.To simplify the ER diagram
D.To enhance query performance
Solution
Normalization is used to eliminate data anomalies and reduce redundancy in database design.
Correct Answer: B — To eliminate data anomalies
Q. What is the purpose of normalization in databases?
A.To increase redundancy
B.To reduce data anomalies
C.To improve performance
D.To simplify queries
Solution
The purpose of normalization in databases is to reduce data anomalies and ensure data integrity.
Correct Answer: B — To reduce data anomalies
Q. What is the purpose of the 'GROUP BY' clause in SQL?
A.To sort the result set
B.To aggregate data across multiple records
C.To filter records
D.To join multiple tables
Solution
'GROUP BY' is used to aggregate data across multiple records, often used with aggregate functions like COUNT, SUM, AVG.
Correct Answer: B — To aggregate data across multiple records
Q. What is the result of applying the first normal form (1NF) to a table?
A.All attributes are atomic
B.No transitive dependencies exist
C.All non-key attributes are dependent on the primary key
D.The table has no duplicate rows
Solution
Applying the first normal form (1NF) ensures that all attributes in a table are atomic, meaning they cannot be divided further.
Correct Answer: A — All attributes are atomic
Q. What is the role of a dimension table in a data warehouse?
A.To store transactional data
B.To provide context to fact data
C.To manage user access
D.To perform data cleansing
Solution
Dimension tables provide context to the fact data, allowing users to analyze the facts in relation to various attributes.
Correct Answer: B — To provide context to fact data
Q. What is the role of a transaction manager in a distributed database?
A.To manage data replication
B.To ensure ACID properties across distributed transactions
C.To handle user authentication
D.To optimize query performance
Solution
The transaction manager in a distributed database ensures that ACID properties (Atomicity, Consistency, Isolation, Durability) are maintained across distributed transactions.
Correct Answer: B — To ensure ACID properties across distributed transactions
Q. What is the role of attributes in an ER model?
A.To define relationships
B.To provide additional information about entities
C.To serve as primary keys
D.To represent constraints
Solution
Attributes provide additional information about entities in an ER model.
Correct Answer: B — To provide additional information about entities
