Professional Data Engineer Practice Test

What this test covers

One concept per question, across the topics Professional Data Engineer draws on.

• Late data handling is governed by allowed lateness and triggers
• Metric choice must reflect the cost of each error type on imbalanced data
• Firestore's client libraries provide offline persistence and automatic synchronisation
• Partitioning is what actually reduces bytes scanned in BigQuery
• Sequential row keys create hotspots because Bigtable distributes contiguous key ranges
• At-least-once delivery makes idempotent consumers a requirement, not an optimisation
• Authorised views let someone query derived results without access to the source
• Dead-letter topics isolate poison messages so the stream keeps moving
• Spanner is the option combining horizontal scale with strong global consistency
• Clustering sorts data within partitions so filters on clustering columns skip blocks
• Continuous replication minimises the cutover window
• Bigtable targets very high throughput key lookups over very large datasets
• Streaming ingestion through a message queue is the standard near-real-time analytics path
• Columnar storage means you pay for the columns you read