Q. What is the role of indexing in a data warehouse?
A.To ensure data integrity
B.To speed up query performance
C.To normalize data
D.To manage user access
Solution
Indexing in a data warehouse is used to speed up query performance by allowing faster data retrieval.
Correct Answer: B — To speed up query performance
Q. What SQL command is used to retrieve data from a database?
A.SELECT
B.GET
C.FETCH
D.RETRIEVE
Solution
The SELECT command is used to retrieve data from a database in SQL.
Correct Answer: A — SELECT
Q. Which architecture is commonly used in a client-server database system?
A.Two-tier architecture
B.Three-tier architecture
C.N-tier architecture
D.All of the above
Solution
All of the above architectures can be used in client-server database systems, depending on the complexity and requirements of the application.
Correct Answer: D — All of the above
Q. Which architecture is commonly used in a DBMS?
A.Two-Tier Architecture
B.Three-Tier Architecture
C.Client-Server Architecture
D.All of the above
Solution
All of the above architectures are commonly used in a DBMS to separate the user interface, application logic, and data storage.
Correct Answer: D — All of the above
Q. Which architecture is commonly used in modern DBMS?
A.Single-tier architecture
B.Two-tier architecture
C.Three-tier architecture
D.Four-tier architecture
Solution
The three-tier architecture is commonly used in modern DBMS, separating the user interface, application logic, and database management.
Correct Answer: C — Three-tier architecture
Q. Which component of a DBMS is responsible for managing data storage?
A.Query Processor
B.Storage Manager
C.Transaction Manager
D.Buffer Manager
Solution
The Storage Manager is responsible for managing data storage in a DBMS.
Correct Answer: B — Storage Manager
Q. Which concurrency control method is commonly used in data warehousing?
A.Pessimistic locking
B.Optimistic locking
C.Two-phase locking
D.Timestamp ordering
Solution
Optimistic locking is often used in data warehousing environments where read operations are more frequent than write operations.
Correct Answer: B — Optimistic locking
Q. Which indexing method allows for faster retrieval of data?
A.Sequential Indexing
B.Hash Indexing
C.B-Tree Indexing
D.Bitmap Indexing
Solution
B-Tree Indexing allows for faster retrieval of data due to its balanced tree structure.
Correct Answer: C — B-Tree Indexing
Q. Which normal form eliminates transitive dependencies?
A.First Normal Form (1NF)
B.Second Normal Form (2NF)
C.Third Normal Form (3NF)
D.Boyce-Codd Normal Form (BCNF)
Solution
The Third Normal Form (3NF) eliminates transitive dependencies in a relational database.
Correct Answer: C — Third Normal Form (3NF)
Q. Which normal form requires that a table is in 1NF and all non-key attributes are fully functionally dependent on the primary key?
A.First Normal Form (1NF)
B.Second Normal Form (2NF)
C.Third Normal Form (3NF)
D.Boyce-Codd Normal Form (BCNF)
Solution
Second Normal Form (2NF) requires that all non-key attributes are fully functionally dependent on the primary key.
Correct Answer: B — Second Normal Form (2NF)
Q. Which of the following best describes a business rule?
A.A guideline for database design
B.A constraint on data values
C.A policy that governs data usage
D.All of the above
Solution
A business rule can be a guideline, a constraint, or a policy regarding data.
Correct Answer: D — All of the above
Q. Which of the following best describes a data mart?
A.A large-scale data warehouse
B.A subset of a data warehouse focused on a specific business area
C.A type of database management system
D.A method for data extraction
Solution
A data mart is a smaller, more focused version of a data warehouse, designed to serve the needs of a specific business area.
Correct Answer: B — A subset of a data warehouse focused on a specific business area
Q. Which of the following best describes data mart?
A.A large-scale data warehouse
B.A subset of a data warehouse
C.A type of operational database
D.A data processing tool
Solution
A data mart is a subset of a data warehouse, often focused on a specific business line or team.
Correct Answer: B — A subset of a data warehouse
Q. Which of the following best describes ETL in the context of data warehousing?
A.Extract, Transform, Load
B.Evaluate, Test, Launch
C.Execute, Transfer, Log
D.Extract, 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. Which of the following describes a 'transaction' in a database?
A.A single operation on the database
B.A sequence of operations treated as a single unit
C.A method of indexing data
D.A way to enforce data integrity
Solution
A transaction is a sequence of operations that are treated as a single unit of work, ensuring data integrity.
Correct Answer: B — A sequence of operations treated as a single unit
Q. Which of the following is a benefit of distributed databases?
A.Increased data redundancy
B.Improved data access speed
C.Simplified database management
D.Reduced data security
Solution
Improved data access speed is a benefit of distributed databases as they can provide faster access to data by locating it closer to the user.
Correct Answer: B — Improved data access speed
Q. Which of the following is a characteristic of a data warehouse?
A.Normalized data structure
B.Real-time data processing
C.Historical data storage
D.Transactional data management
Solution
Data warehouses are characterized by their ability to store historical data for analysis, unlike operational databases which focus on current transactions.
Correct Answer: C — Historical data storage
Q. Which of the following is a characteristic of a relational database?
A.Data is stored in tables
B.Data is stored in files
C.Data is stored in objects
D.Data is stored in arrays
Solution
A characteristic of a relational database is that data is stored in tables.
Correct Answer: A — Data is stored in tables
Q. Which of the following is a characteristic of a transaction in a database?
A.Atomicity
B.Redundancy
C.Isolation
D.Both Atomicity and Isolation
Solution
Transactions in a database are characterized by properties known as ACID: Atomicity, Consistency, Isolation, and Durability.
Correct Answer: D — Both Atomicity and Isolation
Q. Which of the following is a characteristic of a transaction in a DBMS?
A.Atomicity
B.Redundancy
C.Isolation
D.Both Atomicity and Isolation
Solution
A transaction in a DBMS is characterized by Atomicity and Isolation, ensuring that transactions are completed fully or not at all.
Correct Answer: D — Both Atomicity and Isolation
Q. Which of the following is a characteristic of a weak entity?
A.It can exist independently of other entities
B.It has a primary key of its own
C.It relies on a strong entity for its identification
D.It cannot have attributes
Solution
A weak entity relies on a strong entity for its identification and does not have a primary key of its own.
Correct Answer: C — It relies on a strong entity for its identification
Q. Which of the following is a characteristic of a well-designed database?
A.High data redundancy
B.Low data integrity
C.Minimal data anomalies
D.Complex relationships
Solution
A well-designed database should have minimal data anomalies, ensuring data integrity and consistency.
Correct Answer: C — Minimal data anomalies
Q. Which of the following is a common method for ensuring data consistency in a data warehouse?
A.Data replication
B.Data normalization
C.Data denormalization
D.Data partitioning
Solution
Data replication is a common method used to ensure data consistency across different systems in a data warehouse.
Correct Answer: A — Data replication
Q. Which of the following is a method for concurrency control in distributed databases?
A.Two-phase locking
B.Data sharding
C.Indexing
D.Data warehousing
Solution
Two-phase locking is a method for concurrency control in distributed databases that helps prevent conflicts when multiple transactions access the same data.
Correct Answer: A — Two-phase locking
Q. Which of the following is a type of indexing?
A.Clustered Index
B.Non-Clustered Index
C.Full-Text Index
D.All of the above
Solution
All of the above options are types of indexing used to improve the speed of data retrieval operations in a database.
Correct Answer: D — All of the above
Q. Which of the following is a type of SQL join?
A.INNER JOIN
B.OUTER JOIN
C.CROSS JOIN
D.All of the above
Solution
INNER JOIN, OUTER JOIN, and CROSS JOIN are all types of SQL joins used to combine rows from two or more tables.
Correct Answer: D — All of the above
Q. Which of the following is an example of a weak entity?
A.A customer with a unique ID
B.An order that depends on a customer
C.A product with a SKU
D.A department with a manager
Solution
An order that depends on a customer is an example of a weak entity, as it cannot exist without the customer.
Correct Answer: B — An order that depends on a customer
Q. Which of the following is an example of an attribute in an ER model?
A.Customer
B.Orders
C.OrderID
D.Many-to-Many
Solution
OrderID is an example of an attribute in an ER model.
Correct Answer: C — OrderID
Q. Which of the following is NOT a benefit of data warehousing?
A.Improved data quality
B.Enhanced data analysis capabilities
C.Increased transaction speed
D.Consolidated data from multiple sources
Solution
Data warehousing focuses on analytical processing rather than transaction speed, which is a characteristic of operational databases.
Correct Answer: C — Increased transaction speed
Q. Which of the following is NOT a benefit of normalization?
A.Reduced data redundancy
B.Improved data integrity
C.Faster query performance
D.Easier maintenance
Solution
Normalization can sometimes lead to slower query performance due to the need for more joins.
