Denormalization involves combining tables to ________ redundancy and improve ________.

  • Decrease, data consistency
  • Decrease, query performance
  • Increase, data consistency
  • Increase, query performance
Denormalization involves combining tables to increase query performance by reducing the need for joins, which can be resource-intensive. However, this may lead to data redundancy and decreased data consistency.

What distinguishes Apache ORC (Optimized Row Columnar) file format from other file formats in big data storage solutions?

  • Columnar storage and optimization
  • In-memory caching
  • NoSQL data model
  • Row-based compression techniques
Apache ORC (Optimized Row Columnar) file format stands out in big data storage solutions due to its columnar storage approach, which organizes data by column rather than by row. This enables efficient compression and encoding techniques tailored to columnar data, leading to improved query performance and reduced storage footprint. Unlike row-based formats, ORC allows for selective column reads, enhancing query speed for analytical workloads commonly found in big data environments.

Scenario: You are designing an ERD for an online shopping platform. Each product can belong to multiple categories, and each category can have multiple products. What type of relationship would you represent between the "Product" and "Category" entities?

  • Many-to-Many
  • Many-to-One
  • One-to-Many
  • One-to-One
The relationship between "Product" and "Category" entities in this scenario is Many-to-Many, as each product can belong to multiple categories, and each category can have multiple products, forming a many-to-many relationship.

________ is a pattern that temporarily blocks access to a service experiencing a failure, allowing it to recover.

  • Circuit Breaker
  • Load Balancing
  • Rate Limiting
  • Redundancy
The Circuit Breaker pattern is a fault-tolerant design pattern used to manage failures in distributed systems. It temporarily blocks access to a service experiencing a failure, preventing cascading failures and allowing the service to recover. By detecting and isolating faulty components, the Circuit Breaker pattern promotes system stability and resilience, improving overall reliability and performance.

The ________ aspect of a data governance framework refers to the establishment of roles, responsibilities, and decision-making processes.

  • Organizational
  • Procedural
  • Structural
  • Technical
The procedural aspect of a data governance framework focuses on defining the processes, procedures, and workflows for managing data within an organization. This includes establishing roles and responsibilities, defining decision-making processes, and outlining procedures for data quality management, data security, and compliance. A robust procedural framework ensures that data governance policies are implemented effectively, leading to improved data quality, consistency, and reliability.

Scenario: You are working on a project where data quality is paramount. How would you determine the effectiveness of the data cleansing process?

  • Compare data quality metrics before and after cleansing
  • Conduct data profiling and outlier detection
  • Measure data completeness, accuracy, consistency, and timeliness
  • Solicit feedback from stakeholders
Determining the effectiveness of the data cleansing process involves measuring various data quality metrics such as completeness, accuracy, consistency, and timeliness. Comparing data quality metrics before and after cleansing helps assess the impact of cleansing activities on data quality improvement. Data profiling and outlier detection identify anomalies and discrepancies in the data. Soliciting feedback from stakeholders provides insights into their satisfaction with the data quality improvements.

Which data cleansing technique involves filling in missing values in a dataset based on statistical methods?

  • Deduplication
  • Imputation
  • Standardization
  • Tokenization
Imputation is a data cleansing technique that involves filling in missing values in a dataset based on statistical methods such as mean, median, or mode imputation. It helps maintain data integrity and completeness by replacing missing values with estimated values derived from the remaining data. Imputation is commonly used in various domains, including data analysis, machine learning, and business intelligence, to handle missing data effectively and minimize its impact on downstream processes.

What is a Fact Table in Dimensional Modeling?

  • A table that connects dimensions
  • A table that stores descriptive attributes
  • A table that stores historical data
  • A table that stores quantitative, measurable facts
In Dimensional Modeling, a Fact Table stores quantitative, measurable facts about a business process or event. It typically contains foreign keys that reference dimension tables for context.

Which of the following is an example of a workflow orchestration tool commonly used in data engineering?

  • Apache Airflow
  • MySQL
  • Tableau
  • TensorFlow
Apache Airflow is a widely used open-source workflow orchestration tool in the field of data engineering. It provides a platform for defining, scheduling, and monitoring workflows as directed acyclic graphs (DAGs). With features like task dependencies, parallel execution, and extensibility through plugins, Apache Airflow is well-suited for orchestrating data pipelines and managing data workflows in various environments.

Apache Hive provides a SQL-like interface called ________ for querying and analyzing data stored in Hadoop.

  • H-SQL
  • HadoopSQL
  • HiveQL
  • HiveQL Interface
Apache Hive provides a SQL-like interface called HiveQL for querying and analyzing data stored in Hadoop. This interface simplifies data querying for users familiar with SQL.