LFC ETL & Data Integration 1 — Questions and Answers
Question 1: What does ETL stand for in data processing?
- Evaluate, Tag, Load
- Extract, Transfer, Load
- Extract, Transform, Load (Correct answer)
- Encode, Translate, Log
Correct answer: Extract, Transform, Load
ETL stands for Extract, Transform, Load, which is a fundamental data integration process. It involves extracting data from various source systems, transforming it into a clean and consistent format, and then loading it into a target system like a data warehouse or lakehouse for analysis.
Question 2: Why is ETL critical in a lakehouse environment?
- To delay data loading
- To minimize storage costs
- To prepare data for analytics (Correct answer)
- To restrict user access
Correct answer: To prepare data for analytics
ETL is critical in a lakehouse environment because it prepares raw data from diverse sources for analytical consumption. By cleansing, transforming, and structuring the data, ETL ensures it is consistent, accurate, and optimized for performance, enabling reliable business intelligence, data science, and machine learning applications.
Question 3: Which tool is often used for data orchestration in lakehouse platforms?
- TensorFlow
- Apache Airflow (Correct answer)
- Grafana
- Kafka Streams
Correct answer: Apache Airflow
Apache Airflow is a widely used open-source platform for programmatically authoring, scheduling, and monitoring complex data pipelines. In lakehouse platforms, it is frequently employed for data orchestration to manage ETL/ELT workflows, ensuring that data ingestion, transformation, and loading processes run reliably and on schedule.
Question 4: How does ELT differ from ETL in modern architectures?
- Transforms data before extracting
- Loads before transforming (Correct answer)
- Eliminates the transform step
- Requires no schema
Correct answer: Loads before transforming
ELT (Extract, Load, Transform) differs from ETL by loading raw data directly into the target system (like a data lake or lakehouse) before any significant transformations occur. This approach leverages the scalable processing power of modern data platforms for transformations, making it particularly efficient for large datasets and flexible for evolving analytical needs.
Question 5: Which type of data integration supports real-time processing in a lakehouse?
- Batch processing only
- Email ETL
- Streaming integration (Correct answer)
- Manual import
Correct answer: Streaming integration
Streaming integration supports real-time processing in a lakehouse by continuously ingesting and processing data as it is generated, rather than in batches. This enables immediate insights and reactions to events, which is crucial for applications requiring up-to-the-minute data, such as fraud detection or real-time dashboards.
Question 6: What ensures data quality during the ETL process?
- Skipping transform step
- Compressing all data
- Performing validation and cleansing (Correct answer)
- Random data sampling
Correct answer: Performing validation and cleansing
Data quality during the ETL process is primarily ensured by performing validation and cleansing steps. Validation checks data against predefined rules for accuracy and consistency, while cleansing corrects or removes erroneous, incomplete, or duplicate data, ensuring that only high-quality data is loaded for analysis.
What does ETL stand for in data processing?