Data ETL Incremental Loads MCQ Questions with Answers (Latest 2026)

Q1. Which option best describes incremental load?

A. Load only new/changed rows since last run. B. Always full reload. C. Random sampling. D. Pure cache eviction.

Select an answer to check.

Answer: Load only new/changed rows since last run.

Here, Load only new/changed rows since last run. is the right choice. Saves cost and time. It aligns directly with what the question asks about which option best describes incremental load. A quick elimination of partially true options helps confirm it.

Q2. What is the primary purpose of incremental load?

A. Load only new/changed rows since last run. B. Pure cache eviction. C. Random sampling. D. Always full reload.

Select an answer to check.

Answer: Load only new/changed rows since last run.

In this case, Load only new/changed rows since last run. is correct. Saves cost and time. It aligns directly with what the question asks about what is the primary purpose of incremental load. A quick elimination of partially true options helps confirm it.

Q3. Which statement about incremental load is most accurate?

A. Load only new/changed rows since last run. B. Random sampling. C. Pure cache eviction. D. Always full reload.

Select an answer to check.

Answer: Load only new/changed rows since last run.

The best option here is Load only new/changed rows since last run.. Saves cost and time. It aligns directly with what the question asks about which statement about incremental load is most accurate. A quick elimination of partially true options helps confirm it.

Q4. How is incremental load best characterized?

A. Pure cache eviction. B. Always full reload. C. Load only new/changed rows since last run. D. Random sampling.

Select an answer to check.

Answer: Load only new/changed rows since last run.

For this question, Load only new/changed rows since last run. is correct. Saves cost and time. It aligns directly with what the question asks about how is incremental load best characterized. A quick elimination of partially true options helps confirm it.

Q5. Which option best describes a watermark?

A. Highest processed value (timestamp/id). B. A schema constraint. C. A retry counter. D. An index.

Select an answer to check.

Answer: Highest processed value (timestamp/id).

Highest processed value (timestamp/id). is the correct answer here. Drives next run's filter. It aligns directly with what the question asks about which option best describes a watermark. A quick elimination of partially true options helps confirm it.

Q6. What is the primary purpose of a watermark?

A. A retry counter. B. An index. C. Highest processed value (timestamp/id). D. A schema constraint.

Select an answer to check.

Answer: Highest processed value (timestamp/id).

Here, Highest processed value (timestamp/id). is the right choice. Drives next run's filter. This matches the core idea being tested around what is the primary purpose of a watermark. A quick elimination of partially true options helps confirm it.

Q7. Which statement about a watermark is most accurate?

A. An index. B. A retry counter. C. Highest processed value (timestamp/id). D. A schema constraint.

Select an answer to check.

Answer: Highest processed value (timestamp/id).

In this case, Highest processed value (timestamp/id). is correct. Drives next run's filter. This matches the core idea being tested around which statement about a watermark is most accurate. A quick elimination of partially true options helps confirm it.

Q8. How is a watermark best characterized?

A. A schema constraint. B. Highest processed value (timestamp/id). C. An index. D. A retry counter.

Select an answer to check.

Answer: Highest processed value (timestamp/id).

The best option here is Highest processed value (timestamp/id).. Drives next run's filter. This matches the core idea being tested around how is a watermark best characterized. A quick elimination of partially true options helps confirm it.

Q9. Which option best describes CDC-driven incremental?

A. Pure trigger-only. B. Pure manual. C. Pure full reload. D. Stream changes from source log.

Select an answer to check.

Answer: Stream changes from source log.

For this question, Stream changes from source log. is correct. Lower latency option. This matches the core idea being tested around which option best describes cdc-driven incremental. A quick elimination of partially true options helps confirm it.

Q10. What is the primary purpose of CDC-driven incremental?

A. Pure full reload. B. Pure trigger-only. C. Stream changes from source log. D. Pure manual.

Select an answer to check.

Answer: Stream changes from source log.

Stream changes from source log. is the correct answer here. Lower latency option. This matches the core idea being tested around what is the primary purpose of cdc-driven incremental. A quick elimination of partially true options helps confirm it.

Q11. Which statement about CDC-driven incremental is most accurate?

A. Stream changes from source log. B. Pure full reload. C. Pure trigger-only. D. Pure manual.

Select an answer to check.

Answer: Stream changes from source log.

Here, Stream changes from source log. is the right choice. Lower latency option. That is exactly the concept behind which statement about cdc-driven incremental is most accurate in this context. A quick elimination of partially true options helps confirm it.

Q12. How is CDC-driven incremental best characterized?

A. Pure full reload. B. Pure manual. C. Pure trigger-only. D. Stream changes from source log.

Select an answer to check.

Answer: Stream changes from source log.

In this case, Stream changes from source log. is correct. Lower latency option. That is exactly the concept behind how is cdc-driven incremental best characterized in this context. A quick elimination of partially true options helps confirm it.

Q13. Which option best describes query-based incremental?

A. Pure trigger CDC. B. Use updated_at >= watermark. C. Pure log-based CDC. D. Pure full reload.

Select an answer to check.

Answer: Use updated_at >= watermark.

The best option here is Use updated_at >= watermark.. Simple but needs reliable timestamps. That is exactly the concept behind which option best describes query-based incremental in this context. A quick elimination of partially true options helps confirm it.

Q14. What is the primary purpose of query-based incremental?

A. Pure log-based CDC. B. Pure trigger CDC. C. Use updated_at >= watermark. D. Pure full reload.

Select an answer to check.

Answer: Use updated_at >= watermark.

For this question, Use updated_at >= watermark. is correct. Simple but needs reliable timestamps. That is exactly the concept behind what is the primary purpose of query-based incremental in this context. A quick elimination of partially true options helps confirm it.

Q15. Which statement about query-based incremental is most accurate?

A. Pure log-based CDC. B. Pure trigger CDC. C. Pure full reload. D. Use updated_at >= watermark.

Select an answer to check.

Answer: Use updated_at >= watermark.

Use updated_at >= watermark. is the correct answer here. Simple but needs reliable timestamps. That is exactly the concept behind which statement about query-based incremental is most accurate in this context. A quick elimination of partially true options helps confirm it.

Q16. How is query-based incremental best characterized?

A. Pure full reload. B. Pure trigger CDC. C. Use updated_at >= watermark. D. Pure log-based CDC.

Select an answer to check.

Answer: Use updated_at >= watermark.

Here, Use updated_at >= watermark. is the right choice. Simple but needs reliable timestamps. It fits the requirement in the prompt about how is query-based incremental best characterized. A quick elimination of partially true options helps confirm it.

Q17. Which option best describes late-arriving data?

A. Pure dedup issue. B. Always on time. C. Pure schema drift. D. Records arriving after watermark moved.

Select an answer to check.

Answer: Records arriving after watermark moved.

In this case, Records arriving after watermark moved. is correct. Use grace period or reprocess. It fits the requirement in the prompt about which option best describes late-arriving data. A quick elimination of partially true options helps confirm it.

Q18. What is the primary purpose of late-arriving data?

A. Pure dedup issue. B. Always on time. C. Pure schema drift. D. Records arriving after watermark moved.

Select an answer to check.

Answer: Records arriving after watermark moved.

The best option here is Records arriving after watermark moved.. Use grace period or reprocess. It fits the requirement in the prompt about what is the primary purpose of late-arriving data. A quick elimination of partially true options helps confirm it.

Q19. Which statement about late-arriving data is most accurate?

A. Records arriving after watermark moved. B. Always on time. C. Pure schema drift. D. Pure dedup issue.

Select an answer to check.

Answer: Records arriving after watermark moved.

For this question, Records arriving after watermark moved. is correct. Use grace period or reprocess. It fits the requirement in the prompt about which statement about late-arriving data is most accurate. A quick elimination of partially true options helps confirm it.

Q20. How is late-arriving data best characterized?

A. Records arriving after watermark moved. B. Always on time. C. Pure schema drift. D. Pure dedup issue.

Select an answer to check.

Answer: Records arriving after watermark moved.

Records arriving after watermark moved. is the correct answer here. Use grace period or reprocess. It fits the requirement in the prompt about how is late-arriving data best characterized. A quick elimination of partially true options helps confirm it.

Q21. Which option best describes upserts (MERGE)?

A. DELETE-only. B. Insert new and update existing rows by key. C. UPDATE-only loads. D. INSERT-only loads.

Select an answer to check.

Answer: Insert new and update existing rows by key.

Here, Insert new and update existing rows by key. is the right choice. Common for incrementals. This is the most accurate statement for which option best describes upserts (merge). A quick elimination of partially true options helps confirm it.

Q22. What is the primary purpose of upserts (MERGE)?

A. UPDATE-only loads. B. Insert new and update existing rows by key. C. DELETE-only. D. INSERT-only loads.

Select an answer to check.

Answer: Insert new and update existing rows by key.

In this case, Insert new and update existing rows by key. is correct. Common for incrementals. This is the most accurate statement for what is the primary purpose of upserts (merge). A quick elimination of partially true options helps confirm it.

Q23. Which statement about upserts (MERGE) is most accurate?

A. Insert new and update existing rows by key. B. UPDATE-only loads. C. DELETE-only. D. INSERT-only loads.

Select an answer to check.

Answer: Insert new and update existing rows by key.

The best option here is Insert new and update existing rows by key.. Common for incrementals. This is the most accurate statement for which statement about upserts (merge) is most accurate. A quick elimination of partially true options helps confirm it.

Q24. How is upserts (MERGE) best characterized?

A. Insert new and update existing rows by key. B. INSERT-only loads. C. DELETE-only. D. UPDATE-only loads.

Select an answer to check.

Answer: Insert new and update existing rows by key.

For this question, Insert new and update existing rows by key. is correct. Common for incrementals. This is the most accurate statement for how is upserts (merge) best characterized. A quick elimination of partially true options helps confirm it.

Q25. Which option best describes hard deletes vs soft deletes?

A. Both pure indexes. B. Both pure DDL. C. Same thing. D. Remove vs flag deleted=true.

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Answer: Remove vs flag deleted=true.

Remove vs flag deleted=true. is the correct answer here. Soft retains history. This is the most accurate statement for which option best describes hard deletes vs soft. A quick elimination of partially true options helps confirm it.

Q26. What is the primary purpose of hard deletes vs soft deletes?

A. Both pure DDL. B. Both pure indexes. C. Remove vs flag deleted=true. D. Same thing.

Select an answer to check.

Answer: Remove vs flag deleted=true.

Here, Remove vs flag deleted=true. is the right choice. Soft retains history. It aligns directly with what the question asks about what is the primary purpose of hard deletes. The other options are either incomplete or contextually incorrect.

Q27. Which statement about hard deletes vs soft deletes is most accurate?

A. Same thing. B. Remove vs flag deleted=true. C. Both pure DDL. D. Both pure indexes.

Select an answer to check.

Answer: Remove vs flag deleted=true.

In this case, Remove vs flag deleted=true. is correct. Soft retains history. It aligns directly with what the question asks about which statement about hard deletes vs soft deletes. The other options are either incomplete or contextually incorrect.

Q28. How is hard deletes vs soft deletes best characterized?

A. Same thing. B. Both pure DDL. C. Remove vs flag deleted=true. D. Both pure indexes.

Select an answer to check.

Answer: Remove vs flag deleted=true.

The best option here is Remove vs flag deleted=true.. Soft retains history. It aligns directly with what the question asks about how is hard deletes vs soft deletes best. The other options are either incomplete or contextually incorrect.

Q29. Which option best describes change tracking columns?

A. Pure FKs. B. updated_at, version, etag. C. Pure created_at only. D. Pure schema columns only.

Select an answer to check.

Answer: updated_at, version, etag.

For this question, updated_at, version, etag. is correct. Drive incremental queries. It aligns directly with what the question asks about which option best describes change tracking columns. The other options are either incomplete or contextually incorrect.

Q30. What is the primary purpose of change tracking columns?

A. Pure FKs. B. Pure created_at only. C. Pure schema columns only. D. updated_at, version, etag.

Select an answer to check.

Answer: updated_at, version, etag.

updated_at, version, etag. is the correct answer here. Drive incremental queries. It aligns directly with what the question asks about what is the primary purpose of change tracking. The other options are either incomplete or contextually incorrect.

Q31. Which statement about change tracking columns is most accurate?

A. Pure schema columns only. B. Pure FKs. C. updated_at, version, etag. D. Pure created_at only.

Select an answer to check.

Answer: updated_at, version, etag.

Here, updated_at, version, etag. is the right choice. Drive incremental queries. This matches the core idea being tested around which statement about change tracking columns is most. The other options are either incomplete or contextually incorrect.

Q32. How is change tracking columns best characterized?

A. Pure FKs. B. updated_at, version, etag. C. Pure created_at only. D. Pure schema columns only.

Select an answer to check.

Answer: updated_at, version, etag.

In this case, updated_at, version, etag. is correct. Drive incremental queries. This matches the core idea being tested around how is change tracking columns best characterized. The other options are either incomplete or contextually incorrect.

Q33. Which option best describes idempotent merges?

A. Random outcomes. B. Side-effecting on retry. C. Re-running yields same target state. D. Always different.

Select an answer to check.

Answer: Re-running yields same target state.

The best option here is Re-running yields same target state.. Critical for safety. This matches the core idea being tested around which option best describes idempotent merges. The other options are either incomplete or contextually incorrect.

Q34. What is the primary purpose of idempotent merges?

A. Side-effecting on retry. B. Random outcomes. C. Re-running yields same target state. D. Always different.

Select an answer to check.

Answer: Re-running yields same target state.

For this question, Re-running yields same target state. is correct. Critical for safety. This matches the core idea being tested around what is the primary purpose of idempotent merges. The other options are either incomplete or contextually incorrect.

Q35. Which statement about idempotent merges is most accurate?

A. Always different. B. Re-running yields same target state. C. Random outcomes. D. Side-effecting on retry.

Select an answer to check.

Answer: Re-running yields same target state.

Re-running yields same target state. is the correct answer here. Critical for safety. This matches the core idea being tested around which statement about idempotent merges is most accurate. The other options are either incomplete or contextually incorrect.

Q36. How is idempotent merges best characterized?

A. Re-running yields same target state. B. Side-effecting on retry. C. Random outcomes. D. Always different.

Select an answer to check.

Answer: Re-running yields same target state.

Here, Re-running yields same target state. is the right choice. Critical for safety. That is exactly the concept behind how is idempotent merges best characterized in this context. The other options are either incomplete or contextually incorrect.

Q37. Which option best describes dedup on load?

A. Always full reload. B. Insert all blindly. C. Random retries. D. Remove duplicates by key + version.

Select an answer to check.

Answer: Remove duplicates by key + version.

In this case, Remove duplicates by key + version. is correct. Pair with idempotent merge. That is exactly the concept behind which option best describes dedup on load in this context. The other options are either incomplete or contextually incorrect.

Q38. What is the primary purpose of dedup on load?

A. Always full reload. B. Insert all blindly. C. Remove duplicates by key + version. D. Random retries.

Select an answer to check.

Answer: Remove duplicates by key + version.

The best option here is Remove duplicates by key + version.. Pair with idempotent merge. That is exactly the concept behind what is the primary purpose of dedup on in this context. The other options are either incomplete or contextually incorrect.

Q39. Which statement about dedup on load is most accurate?

A. Insert all blindly. B. Remove duplicates by key + version. C. Always full reload. D. Random retries.

Select an answer to check.

Answer: Remove duplicates by key + version.

For this question, Remove duplicates by key + version. is correct. Pair with idempotent merge. That is exactly the concept behind which statement about dedup on load is most in this context. The other options are either incomplete or contextually incorrect.

Q40. How is dedup on load best characterized?

A. Random retries. B. Remove duplicates by key + version. C. Insert all blindly. D. Always full reload.

Select an answer to check.

Answer: Remove duplicates by key + version.

Remove duplicates by key + version. is the correct answer here. Pair with idempotent merge. That is exactly the concept behind how is dedup on load best characterized in this context. The other options are either incomplete or contextually incorrect.

Q41. Which option best describes backfill ranges?

A. Reprocess specific date/key ranges. B. Always full reload only. C. Pure live forward only. D. Random samples.

Select an answer to check.

Answer: Reprocess specific date/key ranges.

Here, Reprocess specific date/key ranges. is the right choice. Tag runs with run_id. It fits the requirement in the prompt about which option best describes backfill ranges. The other options are either incomplete or contextually incorrect.

Q42. What is the primary purpose of backfill ranges?

A. Random samples. B. Always full reload only. C. Pure live forward only. D. Reprocess specific date/key ranges.

Select an answer to check.

Answer: Reprocess specific date/key ranges.

In this case, Reprocess specific date/key ranges. is correct. Tag runs with run_id. It fits the requirement in the prompt about what is the primary purpose of backfill ranges. The other options are either incomplete or contextually incorrect.

Q43. Which statement about backfill ranges is most accurate?

A. Reprocess specific date/key ranges. B. Pure live forward only. C. Random samples. D. Always full reload only.

Select an answer to check.

Answer: Reprocess specific date/key ranges.

The best option here is Reprocess specific date/key ranges.. Tag runs with run_id. It fits the requirement in the prompt about which statement about backfill ranges is most accurate. The other options are either incomplete or contextually incorrect.

Q44. How is backfill ranges best characterized?

A. Random samples. B. Reprocess specific date/key ranges. C. Always full reload only. D. Pure live forward only.

Select an answer to check.

Answer: Reprocess specific date/key ranges.

For this question, Reprocess specific date/key ranges. is correct. Tag runs with run_id. It fits the requirement in the prompt about how is backfill ranges best characterized. The other options are either incomplete or contextually incorrect.

Q45. Which option best describes partition-based incremental?

A. Reload only affected partitions. B. Random sampling. C. Pure index updates. D. Always full reload.

Select an answer to check.

Answer: Reload only affected partitions.

Reload only affected partitions. is the correct answer here. Cheap when partitions align. It fits the requirement in the prompt about which option best describes partition-based incremental. The other options are either incomplete or contextually incorrect.

Q46. What is the primary purpose of partition-based incremental?

A. Random sampling. B. Pure index updates. C. Reload only affected partitions. D. Always full reload.

Select an answer to check.

Answer: Reload only affected partitions.

Here, Reload only affected partitions. is the right choice. Cheap when partitions align. This is the most accurate statement for what is the primary purpose of partition-based incremental. The other options are either incomplete or contextually incorrect.

Q47. Which statement about partition-based incremental is most accurate?

A. Random sampling. B. Reload only affected partitions. C. Always full reload. D. Pure index updates.

Select an answer to check.

Answer: Reload only affected partitions.

In this case, Reload only affected partitions. is correct. Cheap when partitions align. This is the most accurate statement for which statement about partition-based incremental is most accurate. The other options are either incomplete or contextually incorrect.

Q48. How is partition-based incremental best characterized?

A. Pure index updates. B. Reload only affected partitions. C. Always full reload. D. Random sampling.

Select an answer to check.

Answer: Reload only affected partitions.

The best option here is Reload only affected partitions.. Cheap when partitions align. This is the most accurate statement for how is partition-based incremental best characterized. The other options are either incomplete or contextually incorrect.

Q49. Which option best describes checkpointing watermarks?

A. Pure logs only. B. No persistence. C. Pure caches only. D. Persist watermark per source/run.

Select an answer to check.

Answer: Persist watermark per source/run.

For this question, Persist watermark per source/run. is correct. Required for resume. This is the most accurate statement for which option best describes checkpointing watermarks. The other options are either incomplete or contextually incorrect.

Q50. What is the primary purpose of checkpointing watermarks?

A. Pure logs only. B. Pure caches only. C. Persist watermark per source/run. D. No persistence.

Select an answer to check.

Answer: Persist watermark per source/run.

Persist watermark per source/run. is the correct answer here. Required for resume. This is the most accurate statement for what is the primary purpose of checkpointing watermarks. The other options are either incomplete or contextually incorrect.