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 a data mart?
Answer: A subset of a data warehouse focused on a specific business area
A data mart is a focused, department-specific subset of a data warehouse serving a particular business function.
Which processing model handles data in fixed-size chunks at scheduled intervals?
Answer: Batch processing
Batch processing collects and processes data in groups on a schedule rather than continuously.
What is the main advantage of using surrogate keys in a data warehouse?
Answer: They provide stable, system-generated identifiers independent of source-system changes
Surrogate keys are artificial identifiers that stay stable even when source business keys change, simplifying joins and history tracking.
What does 'schema drift' refer to?
Answer: Unexpected changes to the structure of incoming data over time
Schema drift is when the structure of source data changes unexpectedly, potentially breaking downstream pipelines.
Which storage layer pattern often organizes data into bronze, silver, and gold tiers?
Answer: Medallion architecture
The medallion architecture progressively refines data through bronze (raw), silver (cleaned), and gold (curated) layers.
What is the purpose of a dead-letter queue in a streaming pipeline?
Answer: To capture messages that fail processing for later inspection or retry
A dead-letter queue isolates messages that could not be processed so they can be examined or reprocessed without blocking the main flow.
Why is incremental loading often preferred over full reloads?
Answer: It processes only new or changed data, reducing time and resource usage
Incremental loading moves only new or modified records, making pipelines faster and cheaper than reprocessing everything.