Data ETL Advanced MCQ Questions with Answers (Latest 2026)

Q1. Which option best describes late arriving data?

A. Data arriving after its event time. B. Pure schema drift. C. Pure deduplication issue. D. Always on time.

Select an answer to check.

Answer: Data arriving after its event time.

Here, Data arriving after its event time. is the right choice. Watermarks/late tolerance handle it. It aligns directly with what the question asks about which option best describes late arriving data. A quick elimination of partially true options helps confirm it.

Q2. What is the primary purpose of late arriving data?

A. Always on time. B. Pure deduplication issue. C. Pure schema drift. D. Data arriving after its event time.

Select an answer to check.

Answer: Data arriving after its event time.

In this case, Data arriving after its event time. is correct. Watermarks/late tolerance handle it. It aligns directly with what the question asks about what is the primary purpose of late arriving. A quick elimination of partially true options helps confirm it.

Q3. Which statement about late arriving data is most accurate?

A. Pure schema drift. B. Always on time. C. Data arriving after its event time. D. Pure deduplication issue.

Select an answer to check.

Answer: Data arriving after its event time.

The best option here is Data arriving after its event time.. Watermarks/late tolerance handle it. It aligns directly with what the question asks about which statement about late arriving data is most. A quick elimination of partially true options helps confirm it.

Q4. How is late arriving data best characterized?

A. Pure deduplication issue. B. Data arriving after its event time. C. Pure schema drift. D. Always on time.

Select an answer to check.

Answer: Data arriving after its event time.

For this question, Data arriving after its event time. is correct. Watermarks/late tolerance handle it. It aligns directly with what the question asks about how is late arriving data best characterized. A quick elimination of partially true options helps confirm it.

Q5. Which option best describes late arriving dimensions?

A. A pure fact issue. B. A pure unique constraint issue. C. Dim record arrives after fact references it. D. Pure schema mismatch.

Select an answer to check.

Answer: Dim record arrives after fact references it.

Dim record arrives after fact references it. is the correct answer here. Use placeholders or reprocess. It aligns directly with what the question asks about which option best describes late arriving dimensions. A quick elimination of partially true options helps confirm it.

Q6. What is the primary purpose of late arriving dimensions?

A. Pure schema mismatch. B. A pure unique constraint issue. C. Dim record arrives after fact references it. D. A pure fact issue.

Select an answer to check.

Answer: Dim record arrives after fact references it.

Here, Dim record arrives after fact references it. is the right choice. Use placeholders or reprocess. This matches the core idea being tested around what is the primary purpose of late arriving. A quick elimination of partially true options helps confirm it.

Q7. Which statement about late arriving dimensions is most accurate?

A. Pure schema mismatch. B. A pure fact issue. C. A pure unique constraint issue. D. Dim record arrives after fact references it.

Select an answer to check.

Answer: Dim record arrives after fact references it.

In this case, Dim record arrives after fact references it. is correct. Use placeholders or reprocess. This matches the core idea being tested around which statement about late arriving dimensions is most. A quick elimination of partially true options helps confirm it.

Q8. How is late arriving dimensions best characterized?

A. Dim record arrives after fact references it. B. Pure schema mismatch. C. A pure fact issue. D. A pure unique constraint issue.

Select an answer to check.

Answer: Dim record arrives after fact references it.

The best option here is Dim record arrives after fact references it.. Use placeholders or reprocess. This matches the core idea being tested around how is late arriving dimensions best characterized. A quick elimination of partially true options helps confirm it.

Q9. Which option best describes idempotent merge?

A. Pure TRUNCATE only. B. Pure DELETE only. C. Plain INSERT only. D. MERGE/UPSERT designed safe under retry.

Select an answer to check.

Answer: MERGE/UPSERT designed safe under retry.

For this question, MERGE/UPSERT designed safe under retry. is correct. Key + version pattern. This matches the core idea being tested around which option best describes idempotent merge. A quick elimination of partially true options helps confirm it.

Q10. What is the primary purpose of idempotent merge?

A. Plain INSERT only. B. Pure TRUNCATE only. C. MERGE/UPSERT designed safe under retry. D. Pure DELETE only.

Select an answer to check.

Answer: MERGE/UPSERT designed safe under retry.

MERGE/UPSERT designed safe under retry. is the correct answer here. Key + version pattern. This matches the core idea being tested around what is the primary purpose of idempotent merge. A quick elimination of partially true options helps confirm it.

Q11. Which statement about idempotent merge is most accurate?

A. MERGE/UPSERT designed safe under retry. B. Plain INSERT only. C. Pure DELETE only. D. Pure TRUNCATE only.

Select an answer to check.

Answer: MERGE/UPSERT designed safe under retry.

Here, MERGE/UPSERT designed safe under retry. is the right choice. Key + version pattern. That is exactly the concept behind which statement about idempotent merge is most accurate in this context. A quick elimination of partially true options helps confirm it.

Q12. How is idempotent merge best characterized?

A. Pure DELETE only. B. Pure TRUNCATE only. C. MERGE/UPSERT designed safe under retry. D. Plain INSERT only.

Select an answer to check.

Answer: MERGE/UPSERT designed safe under retry.

In this case, MERGE/UPSERT designed safe under retry. is correct. Key + version pattern. That is exactly the concept behind how is idempotent merge best characterized in this context. A quick elimination of partially true options helps confirm it.

Q13. Which option best describes CDC log-based?

A. Read DB transaction log for changes. B. Pure manual exports. C. Pure trigger-based only. D. Periodic full snapshot only.

Select an answer to check.

Answer: Read DB transaction log for changes.

The best option here is Read DB transaction log for changes.. Lower DB impact. That is exactly the concept behind which option best describes cdc log-based in this context. A quick elimination of partially true options helps confirm it.

Q14. What is the primary purpose of CDC log-based?

A. Pure manual exports. B. Periodic full snapshot only. C. Pure trigger-based only. D. Read DB transaction log for changes.

Select an answer to check.

Answer: Read DB transaction log for changes.

For this question, Read DB transaction log for changes. is correct. Lower DB impact. That is exactly the concept behind what is the primary purpose of cdc log-based in this context. A quick elimination of partially true options helps confirm it.

Q15. Which statement about CDC log-based is most accurate?

A. Periodic full snapshot only. B. Read DB transaction log for changes. C. Pure trigger-based only. D. Pure manual exports.

Select an answer to check.

Answer: Read DB transaction log for changes.

Read DB transaction log for changes. is the correct answer here. Lower DB impact. That is exactly the concept behind which statement about cdc log-based is most accurate in this context. A quick elimination of partially true options helps confirm it.

Q16. How is CDC log-based best characterized?

A. Pure trigger-based only. B. Read DB transaction log for changes. C. Periodic full snapshot only. D. Pure manual exports.

Select an answer to check.

Answer: Read DB transaction log for changes.

Here, Read DB transaction log for changes. is the right choice. Lower DB impact. It fits the requirement in the prompt about how is cdc log-based best characterized. A quick elimination of partially true options helps confirm it.

Q17. Which option best describes CDC trigger-based?

A. Pure full reload. B. Pure log-based. C. Pure manual export. D. DB triggers write change events.

Select an answer to check.

Answer: DB triggers write change events.

In this case, DB triggers write change events. is correct. Adds load to source. It fits the requirement in the prompt about which option best describes cdc trigger-based. A quick elimination of partially true options helps confirm it.

Q18. What is the primary purpose of CDC trigger-based?

A. Pure full reload. B. Pure manual export. C. Pure log-based. D. DB triggers write change events.

Select an answer to check.

Answer: DB triggers write change events.

The best option here is DB triggers write change events.. Adds load to source. It fits the requirement in the prompt about what is the primary purpose of cdc trigger-based. A quick elimination of partially true options helps confirm it.

Q19. Which statement about CDC trigger-based is most accurate?

A. Pure log-based. B. DB triggers write change events. C. Pure full reload. D. Pure manual export.

Select an answer to check.

Answer: DB triggers write change events.

For this question, DB triggers write change events. is correct. Adds load to source. It fits the requirement in the prompt about which statement about cdc trigger-based is most accurate. A quick elimination of partially true options helps confirm it.

Q20. How is CDC trigger-based best characterized?

A. Pure log-based. B. Pure manual export. C. Pure full reload. D. DB triggers write change events.

Select an answer to check.

Answer: DB triggers write change events.

DB triggers write change events. is the correct answer here. Adds load to source. It fits the requirement in the prompt about how is cdc trigger-based best characterized. A quick elimination of partially true options helps confirm it.

Q21. Which option best describes medallion architecture?

A. Pure snowflake schema. B. Single bronze layer only. C. Pure star schema. D. Bronze/Silver/Gold lake layers.

Select an answer to check.

Answer: Bronze/Silver/Gold lake layers.

Here, Bronze/Silver/Gold lake layers. is the right choice. Lakehouse layered model. This is the most accurate statement for which option best describes medallion architecture. A quick elimination of partially true options helps confirm it.

Q22. What is the primary purpose of medallion architecture?

A. Single bronze layer only. B. Bronze/Silver/Gold lake layers. C. Pure star schema. D. Pure snowflake schema.

Select an answer to check.

Answer: Bronze/Silver/Gold lake layers.

In this case, Bronze/Silver/Gold lake layers. is correct. Lakehouse layered model. This is the most accurate statement for what is the primary purpose of medallion architecture. A quick elimination of partially true options helps confirm it.

Q23. Which statement about medallion architecture is most accurate?

A. Single bronze layer only. B. Bronze/Silver/Gold lake layers. C. Pure star schema. D. Pure snowflake schema.

Select an answer to check.

Answer: Bronze/Silver/Gold lake layers.

The best option here is Bronze/Silver/Gold lake layers.. Lakehouse layered model. This is the most accurate statement for which statement about medallion architecture is most accurate. A quick elimination of partially true options helps confirm it.

Q24. How is medallion architecture best characterized?

A. Bronze/Silver/Gold lake layers. B. Pure snowflake schema. C. Pure star schema. D. Single bronze layer only.

Select an answer to check.

Answer: Bronze/Silver/Gold lake layers.

For this question, Bronze/Silver/Gold lake layers. is correct. Lakehouse layered model. This is the most accurate statement for how is medallion architecture best characterized. A quick elimination of partially true options helps confirm it.

Q25. Which option best describes data lakehouse?

A. Lake + warehouse semantics together. B. A pure data lake. C. A pure messaging broker. D. A pure relational warehouse.

Select an answer to check.

Answer: Lake + warehouse semantics together.

Lake + warehouse semantics together. is the correct answer here. Delta/Iceberg/Hudi. This is the most accurate statement for which option best describes data lakehouse. A quick elimination of partially true options helps confirm it.

Q26. What is the primary purpose of data lakehouse?

A. A pure relational warehouse. B. A pure messaging broker. C. Lake + warehouse semantics together. D. A pure data lake.

Select an answer to check.

Answer: Lake + warehouse semantics together.

Here, Lake + warehouse semantics together. is the right choice. Delta/Iceberg/Hudi. It aligns directly with what the question asks about what is the primary purpose of data lakehouse. The other options are either incomplete or contextually incorrect.

Q27. Which statement about data lakehouse is most accurate?

A. A pure relational warehouse. B. A pure data lake. C. Lake + warehouse semantics together. D. A pure messaging broker.

Select an answer to check.

Answer: Lake + warehouse semantics together.

In this case, Lake + warehouse semantics together. is correct. Delta/Iceberg/Hudi. It aligns directly with what the question asks about which statement about data lakehouse is most accurate. The other options are either incomplete or contextually incorrect.

Q28. How is data lakehouse best characterized?

A. A pure messaging broker. B. Lake + warehouse semantics together. C. A pure relational warehouse. D. A pure data lake.

Select an answer to check.

Answer: Lake + warehouse semantics together.

The best option here is Lake + warehouse semantics together.. Delta/Iceberg/Hudi. It aligns directly with what the question asks about how is data lakehouse best characterized. The other options are either incomplete or contextually incorrect.

Q29. Which option best describes ACID on lakes?

A. Pure eventually-consistent. B. Transactional layer on object storage. C. Pure read-only. D. Pure best-effort.

Select an answer to check.

Answer: Transactional layer on object storage.

For this question, Transactional layer on object storage. is correct. Delta/Iceberg/Hudi provide this. It aligns directly with what the question asks about which option best describes acid on lakes. The other options are either incomplete or contextually incorrect.

Q30. What is the primary purpose of ACID on lakes?

A. Pure eventually-consistent. B. Pure best-effort. C. Transactional layer on object storage. D. Pure read-only.

Select an answer to check.

Answer: Transactional layer on object storage.

Transactional layer on object storage. is the correct answer here. Delta/Iceberg/Hudi provide this. It aligns directly with what the question asks about what is the primary purpose of acid on. The other options are either incomplete or contextually incorrect.

Q31. Which statement about ACID on lakes is most accurate?

A. Pure best-effort. B. Pure eventually-consistent. C. Pure read-only. D. Transactional layer on object storage.

Select an answer to check.

Answer: Transactional layer on object storage.

Here, Transactional layer on object storage. is the right choice. Delta/Iceberg/Hudi provide this. This matches the core idea being tested around which statement about acid on lakes is most. The other options are either incomplete or contextually incorrect.

Q32. How is ACID on lakes best characterized?

A. Pure read-only. B. Pure best-effort. C. Pure eventually-consistent. D. Transactional layer on object storage.

Select an answer to check.

Answer: Transactional layer on object storage.

In this case, Transactional layer on object storage. is correct. Delta/Iceberg/Hudi provide this. This matches the core idea being tested around how is acid on lakes best characterized. The other options are either incomplete or contextually incorrect.

Q33. Which option best describes schema evolution?

A. Always full re-ingest. B. Pure manual migrations. C. Add/modify columns without breaking pipelines. D. Schema is frozen.

Select an answer to check.

Answer: Add/modify columns without breaking pipelines.

The best option here is Add/modify columns without breaking pipelines.. Forward/backward compat. This matches the core idea being tested around which option best describes schema evolution. The other options are either incomplete or contextually incorrect.

Q34. What is the primary purpose of schema evolution?

A. Add/modify columns without breaking pipelines. B. Schema is frozen. C. Always full re-ingest. D. Pure manual migrations.

Select an answer to check.

Answer: Add/modify columns without breaking pipelines.

For this question, Add/modify columns without breaking pipelines. is correct. Forward/backward compat. This matches the core idea being tested around what is the primary purpose of schema evolution. The other options are either incomplete or contextually incorrect.

Q35. Which statement about schema evolution is most accurate?

A. Schema is frozen. B. Add/modify columns without breaking pipelines. C. Pure manual migrations. D. Always full re-ingest.

Select an answer to check.

Answer: Add/modify columns without breaking pipelines.

Add/modify columns without breaking pipelines. is the correct answer here. Forward/backward compat. This matches the core idea being tested around which statement about schema evolution is most accurate. The other options are either incomplete or contextually incorrect.

Q36. How is schema evolution best characterized?

A. Pure manual migrations. B. Add/modify columns without breaking pipelines. C. Schema is frozen. D. Always full re-ingest.

Select an answer to check.

Answer: Add/modify columns without breaking pipelines.

Here, Add/modify columns without breaking pipelines. is the right choice. Forward/backward compat. That is exactly the concept behind how is schema evolution best characterized in this context. The other options are either incomplete or contextually incorrect.

Q37. Which option best describes partition pruning?

A. Always full scan. B. Pure index seek. C. Skip partitions that don't match filters. D. Random sampling.

Select an answer to check.

Answer: Skip partitions that don't match filters.

In this case, Skip partitions that don't match filters. is correct. Big I/O reduction. That is exactly the concept behind which option best describes partition pruning in this context. The other options are either incomplete or contextually incorrect.

Q38. What is the primary purpose of partition pruning?

A. Skip partitions that don't match filters. B. Pure index seek. C. Random sampling. D. Always full scan.

Select an answer to check.

Answer: Skip partitions that don't match filters.

The best option here is Skip partitions that don't match filters.. Big I/O reduction. That is exactly the concept behind what is the primary purpose of partition pruning in this context. The other options are either incomplete or contextually incorrect.

Q39. Which statement about partition pruning is most accurate?

A. Pure index seek. B. Always full scan. C. Random sampling. D. Skip partitions that don't match filters.

Select an answer to check.

Answer: Skip partitions that don't match filters.

For this question, Skip partitions that don't match filters. is correct. Big I/O reduction. That is exactly the concept behind which statement about partition pruning is most accurate in this context. The other options are either incomplete or contextually incorrect.

Q40. How is partition pruning best characterized?

A. Random sampling. B. Skip partitions that don't match filters. C. Always full scan. D. Pure index seek.

Select an answer to check.

Answer: Skip partitions that don't match filters.

Skip partitions that don't match filters. is the correct answer here. Big I/O reduction. That is exactly the concept behind how is partition pruning best characterized in this context. The other options are either incomplete or contextually incorrect.

Q41. Which option best describes z-ordering / clustering?

A. Random ordering. B. Pure indexing only. C. Pure partitioning only. D. Co-locate related data in files.

Select an answer to check.

Answer: Co-locate related data in files.

Here, Co-locate related data in files. is the right choice. Improves selective scans. It fits the requirement in the prompt about which option best describes z-ordering / clustering. The other options are either incomplete or contextually incorrect.

Q42. What is the primary purpose of z-ordering / clustering?

A. Co-locate related data in files. B. Pure indexing only. C. Random ordering. D. Pure partitioning only.

Select an answer to check.

Answer: Co-locate related data in files.

In this case, Co-locate related data in files. is correct. Improves selective scans. It fits the requirement in the prompt about what is the primary purpose of z-ordering /. The other options are either incomplete or contextually incorrect.

Q43. Which statement about z-ordering / clustering is most accurate?

A. Pure indexing only. B. Random ordering. C. Co-locate related data in files. D. Pure partitioning only.

Select an answer to check.

Answer: Co-locate related data in files.

The best option here is Co-locate related data in files.. Improves selective scans. It fits the requirement in the prompt about which statement about z-ordering / clustering is most. The other options are either incomplete or contextually incorrect.

Q44. How is z-ordering / clustering best characterized?

A. Co-locate related data in files. B. Pure indexing only. C. Random ordering. D. Pure partitioning only.

Select an answer to check.

Answer: Co-locate related data in files.

For this question, Co-locate related data in files. is correct. Improves selective scans. It fits the requirement in the prompt about how is z-ordering / clustering best characterized. The other options are either incomplete or contextually incorrect.

Q45. Which option best describes file compaction?

A. Combine small files for efficiency. B. Pure deletion. C. Always many small files. D. Pure rewrites of single rows.

Select an answer to check.

Answer: Combine small files for efficiency.

Combine small files for efficiency. is the correct answer here. Reduces metadata overhead. It fits the requirement in the prompt about which option best describes file compaction. The other options are either incomplete or contextually incorrect.

Q46. What is the primary purpose of file compaction?

A. Combine small files for efficiency. B. Pure rewrites of single rows. C. Pure deletion. D. Always many small files.

Select an answer to check.

Answer: Combine small files for efficiency.

Here, Combine small files for efficiency. is the right choice. Reduces metadata overhead. This is the most accurate statement for what is the primary purpose of file compaction. The other options are either incomplete or contextually incorrect.

Q47. Which statement about file compaction is most accurate?

A. Pure deletion. B. Combine small files for efficiency. C. Always many small files. D. Pure rewrites of single rows.

Select an answer to check.

Answer: Combine small files for efficiency.

In this case, Combine small files for efficiency. is correct. Reduces metadata overhead. This is the most accurate statement for which statement about file compaction is most accurate. The other options are either incomplete or contextually incorrect.

Q48. How is file compaction best characterized?

A. Always many small files. B. Pure deletion. C. Combine small files for efficiency. D. Pure rewrites of single rows.

Select an answer to check.

Answer: Combine small files for efficiency.

The best option here is Combine small files for efficiency.. Reduces metadata overhead. This is the most accurate statement for how is file compaction best characterized. The other options are either incomplete or contextually incorrect.

Q49. Which option best describes vacuuming?

A. A pure schema change. B. A pure backup. C. A pure index rebuild. D. Remove old/unused data files (with retention).

Select an answer to check.

Answer: Remove old/unused data files (with retention).

For this question, Remove old/unused data files (with retention). is correct. Required for cost control. This is the most accurate statement for which option best describes vacuuming. The other options are either incomplete or contextually incorrect.

Q50. What is the primary purpose of vacuuming?

A. A pure backup. B. A pure schema change. C. A pure index rebuild. D. Remove old/unused data files (with retention).

Select an answer to check.

Answer: Remove old/unused data files (with retention).

Remove old/unused data files (with retention). is the correct answer here. Required for cost control. This is the most accurate statement for what is the primary purpose of vacuuming. The other options are either incomplete or contextually incorrect.