Can you identify any specific scenarios where denormalization can lead to performance improvements over normalization?

  • Complex data relationships
  • OLAP (Online Analytical Processing) scenarios
  • OLTP (Online Transaction Processing) scenarios
  • Reporting and analytical queries
Denormalization can improve performance in scenarios such as reporting and analytical queries where data retrieval from multiple tables is common, as it reduces the need for complex joins and improves query performance.

The process of preparing and organizing data for analysis in a Data Lake is known as ________.

  • Data Cleansing
  • Data Ingestion
  • Data Wrangling
  • ETL
Data Wrangling is the process of preparing and organizing raw data for analysis in a Data Lake. It involves cleaning, transforming, and structuring the data to make it suitable for various analytical tasks.

________ is a key principle of data governance frameworks, ensuring that data is accessible only to authorized users.

  • Availability
  • Confidentiality
  • Integrity
  • Security
Confidentiality is a key principle of data governance frameworks, ensuring that data is accessible only to authorized users and protected from unauthorized access, disclosure, and modification. This involves implementing access controls, encryption, authentication mechanisms, and data masking techniques to safeguard sensitive information and preserve privacy. By maintaining confidentiality, organizations can mitigate the risk of data breaches, unauthorized disclosures, and regulatory non-compliance, thereby preserving trust and integrity in their data assets.

In a distributed NoSQL database, what is the significance of eventual consistency?

  • Delays data availability until all nodes are consistent
  • Ensures immediate consistency across all nodes
  • Prioritizes availability over immediate consistency
  • Prioritizes consistency over availability
Eventual consistency in a distributed NoSQL database means that while data updates may be propagated asynchronously, the system eventually converges to a consistent state, prioritizing availability over immediate consistency.

________ is a data transformation technique that involves aggregating data over specified time intervals.

  • Data Denormalization
  • Data Interpolation
  • Data Normalization
  • Data Summarization
Data Summarization is the process of aggregating data over specified time intervals, such as hours, days, or months, to provide insights into trends and patterns. It's essential in time-series data analysis.

What are the key features of Google Cloud Bigtable that make it suitable for storing and processing large amounts of data?

  • Data warehousing capabilities
  • Relational data storage
  • Scalability, low latency, and high throughput
  • Strong consistency model
Google Cloud Bigtable is designed for storing and processing large amounts of data with a focus on scalability, low latency, and high throughput. It provides a distributed, NoSQL database service that offers automatic scaling to handle massive workloads seamlessly. Bigtable's architecture, inspired by Google's internal technologies, enables horizontal scaling and efficient data distribution, making it well-suited for applications requiring real-time analytics, time-series data, and high-volume transaction processing. Its eventual consistency model and integration with Google Cloud ecosystem further enhance its capabilities for big data use cases.

What is the purpose of Kafka Connect in Apache Kafka?

  • To integrate Kafka with external systems
  • To manage Kafka topics
  • To monitor Kafka cluster
  • To optimize Kafka performance
Kafka Connect is used to integrate Kafka with external systems, allowing seamless data transfer between Kafka and various data sources.

A ________ is a dimension table that contains hierarchies, such as time, geography, or product.

  • Conformed dimension
  • Degenerate dimension
  • Hierarchical dimension
  • Role-playing dimension
A Role-playing dimension is a dimension table that contains hierarchies, such as time, geography, or product, which can be used in multiple roles within the same data warehouse schema, allowing for flexible and efficient querying and analysis across different perspectives.

Scenario: Your company is implementing a data warehouse to analyze sales data from multiple regions. As part of the design process, you need to determine the appropriate schema for the fact and dimension tables. Which schema would you most likely choose and why?

  • Bridge schema
  • Fact constellation schema
  • Snowflake schema
  • Star schema
In this scenario, a Star schema would be the most appropriate choice. It consists of one or more fact tables referencing any number of dimension tables, forming a star-like structure. This schema simplifies queries and ensures better performance due to denormalization, making it suitable for analytical purposes like analyzing sales data across multiple dimensions.

In normalization, the process of breaking down a large table into smaller tables to reduce data redundancy and improve data integrity is called ________.

  • Aggregation
  • Decomposition
  • Denormalization
  • Normalization
Decomposition is the process in normalization where a large table is broken down into smaller tables to reduce redundancy and improve data integrity by eliminating anomalies.