Fundamentals Flashcards
7 cards from real Data Engineering practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Fundamentals flashcards as text
What is data lineage?
Answer: The tracking of data's origin, movement, and transformations through systems
Data lineage documents where data comes from and how it flows and changes across the pipeline.
Which approach best handles late-arriving data in a streaming pipeline?
Answer: Using watermarks and windowing to account for event-time delays
Watermarks combined with event-time windows allow streaming systems to correctly handle records that arrive late.
What is the purpose of a staging area in a data warehouse load process?
Answer: To temporarily hold raw extracted data before transformation and loading
A staging area is intermediate storage where raw data lands before being cleaned, transformed, and loaded.
Which statement about a primary key is correct?
Answer: It uniquely identifies each row and cannot be NULL
A primary key uniquely identifies every row in a table and must be unique and non-null.
What does horizontal scaling (scaling out) mean for a data system?
Answer: Adding more machines or nodes to distribute the load
Horizontal scaling adds more nodes to share the workload, as opposed to upgrading a single machine (vertical scaling).
Why are data quality checks important in a pipeline?
Answer: They detect issues like nulls, duplicates, and schema drift before bad data spreads downstream
Data quality checks catch anomalies early so corrupted or invalid data does not propagate to downstream consumers.
What is denormalization typically used for in analytical data models?
Answer: Improving read/query performance by reducing the number of joins
Denormalization adds redundancy to reduce joins, which speeds up read-heavy analytical queries.