Google Professional Data Engineer Practice Test 15
Question 140
A combined diagnosis-and-remediation review examines: A large Spark cluster remains at peak worker count during long idle stages because autoscaling is disabled. Which investigation followed by action BEST resolves the concern?
- Review object access frequency, retention, retrieval cost, and lifecycle rules. Then Assign storage classes and transitions based on measured access patterns and compliance.
- Inspect BigQuery job statistics, query projections, filters, and data partitions. Then Rewrite queries to project required fields and prune partitions with cost monitoring.
- Inspect Dataproc CPU usage, YARN metrics, cluster autoscaling settings, and job boundaries. Then Apply a supported autoscaling policy or job-based execution with performance safeguards.
- Review reservation assignments, edition capacity, slot utilization, and job priorities. Then Choose an appropriate BigQuery Editions reservation arrangement and workload assignments.
Explanation
Correct Answer
C:Inspect Dataproc CPU usage, YARN metrics, cluster autoscaling settings, and job boundaries. Then Apply a supported autoscaling policy or job-based execution with performance safeguards. This sequence identifies the specific defect and follows it with an appropriate corrective change. Elastic batch processing should match provisioned workers to actual parallel workload demand. Acceptance check: A workload trial meets its deadline while unnecessary idle worker-hours decline.
Incorrect Answers
A:Review object access frequency, retention, retrieval cost, and lifecycle rules. Then Assign storage classes and transitions based on measured access patterns and compliance. This addresses a different situation: A media archive changes every object to the coldest storage class even though analysts read recent objects daily. The current scenario instead calls for the more directly applicable diagnosis and action: Inspect Dataproc CPU usage, YARN metrics, cluster autoscaling settings, and job boundaries. Then Apply a supported autoscaling policy or job-based execution with performance safeguards. The reason is that elastic batch processing should match provisioned workers to actual parallel workload demand.
B:Inspect BigQuery job statistics, query projections, filters, and data partitions. Then Rewrite queries to project required fields and prune partitions with cost monitoring. This addresses a different situation: A reporting application repeatedly runs SELECT star against a wide event table and billing spikes even though it needs five fields. The current scenario instead calls for the more directly applicable diagnosis and action: Inspect Dataproc CPU usage, YARN metrics, cluster autoscaling settings, and job boundaries. Then Apply a supported autoscaling policy or job-based execution with performance safeguards. The reason is that elastic batch processing should match provisioned workers to actual parallel workload demand.
D:Review reservation assignments, edition capacity, slot utilization, and job priorities. Then Choose an appropriate BigQuery Editions reservation arrangement and workload assignments. This addresses a different situation: Critical dashboards compete with scheduled ETL jobs for BigQuery slots and miss interactive latency targets. The current scenario instead calls for the more directly applicable diagnosis and action: Inspect Dataproc CPU usage, YARN metrics, cluster autoscaling settings, and job boundaries. Then Apply a supported autoscaling policy or job-based execution with performance safeguards. The reason is that elastic batch processing should match provisioned workers to actual parallel workload demand.
Question 141
Before modifying the data platform, the team observes: A critical Pub/Sub-to-warehouse flow has a secondary-region deployment template but no retained state, failover routing, or test exercise. Which evidence should the engineer examine FIRST?
- Inspect affected partitions, ingestion manifests, validation history, and recovery sources.
- Inspect source retention, worker state, destination location, regional permissions, and documented steps.
- Inspect dataset locations, backup/copy capabilities, recovery targets, and permitted residency.
- Review availability configuration, application connection recovery, backups, and zone dependencies.
Explanation
Correct Answer
B:Inspect source retention, worker state, destination location, regional permissions, and documented steps. This evidence directly tests the uncertain part of the described system. Disaster-recovery readiness requires explicit source replay, state reconciliation, and executable failover runbooks. A controlled response is: Develop a tested regional recovery workflow with replay controls and data reconciliation.
Incorrect Answers
A:Inspect affected partitions, ingestion manifests, validation history, and recovery sources. This addresses a different situation: An upstream vendor accidentally publishes a corrupted schema version and downstream totals become wrong before anyone notices. The current scenario instead calls for the more directly applicable investigation: Inspect source retention, worker state, destination location, regional permissions, and documented steps. The reason is that disaster-recovery readiness requires explicit source replay, state reconciliation, and executable failover runbooks.
C:Inspect dataset locations, backup/copy capabilities, recovery targets, and permitted residency. This addresses a different situation: A finance warehouse needs recoverable reporting after regional disruption but keeps its only critical dataset in one region. The current scenario instead calls for the more directly applicable investigation: Inspect source retention, worker state, destination location, regional permissions, and documented steps. The reason is that disaster-recovery readiness requires explicit source replay, state reconciliation, and executable failover runbooks.
D:Review availability configuration, application connection recovery, backups, and zone dependencies. This addresses a different situation: A production relational data source resides on a single-zone Cloud SQL instance and a zone outage stops all ingestion. The current scenario instead calls for the more directly applicable investigation: Inspect source retention, worker state, destination location, regional permissions, and documented steps. The reason is that disaster-recovery readiness requires explicit source replay, state reconciliation, and executable failover runbooks.
Question 142
Before modifying the data platform, the team observes: A popular dashboard repeatedly computes the same large daily summary with strict latency goals, while raw transactional records remain necessary for detail drill-down. Which evidence should the engineer examine FIRST?
- Inspect metric definitions, entity keys, report grain, and slowly changing attributes.
- Inspect frequent aggregations, dashboard latency, update frequency, and BigQuery feature support.
- Inspect change-watermarks, partition dates, correction frequency, and merge costs.
- Review source change history, effective timestamps, invoice event times, and model grain.
Explanation
Correct Answer
B:Inspect frequent aggregations, dashboard latency, update frequency, and BigQuery feature support. This evidence directly tests the uncertain part of the described system. Precomputed summary structures can improve repeated analytical response time where refresh limits and query patterns fit. A controlled response is: Evaluate an eligible materialized view or governed summary table for common aggregates.
Incorrect Answers
A:Inspect metric definitions, entity keys, report grain, and slowly changing attributes. This addresses a different situation: A retailer mixes orders, customers, products, and daily inventory measures in one wide duplicated table, making every report join and aggregate inconsistently. The current scenario instead calls for the more directly applicable investigation: Inspect frequent aggregations, dashboard latency, update frequency, and BigQuery feature support. The reason is that precomputed summary structures can improve repeated analytical response time where refresh limits and query patterns fit.
C:Inspect change-watermarks, partition dates, correction frequency, and merge costs. This addresses a different situation: A daily fact table receives corrections, but each load recomputes every historical year and causes excessive query cost. The current scenario instead calls for the more directly applicable investigation: Inspect frequent aggregations, dashboard latency, update frequency, and BigQuery feature support. The reason is that precomputed summary structures can improve repeated analytical response time where refresh limits and query patterns fit.
D:Review source change history, effective timestamps, invoice event times, and model grain. This addresses a different situation: Customer account tiers change over time but year-old invoices must be reported using the tier effective at the invoice date. The current scenario instead calls for the more directly applicable investigation: Inspect frequent aggregations, dashboard latency, update frequency, and BigQuery feature support. The reason is that precomputed summary structures can improve repeated analytical response time where refresh limits and query patterns fit.
Question 143
After applying the change, the team re-examines this condition: A regional processing failure stops daily regulatory datasets because all staging, computation, and recovery copies reside in one failure domain. Which result BEST verifies the improvement?
- A late stale update cannot replace a newer approved customer record.
- Replaying the same business event does not increase recognized revenue a second time.
- A failed exchange-rate refresh prevents publication of a misleading monthly revenue result.
- A planned regional outage test restores processing and meets documented recovery objectives.
Explanation
Correct Answer
D:A planned regional outage test restores processing and meets documented recovery objectives. This measures the intended corrected behavior rather than only confirming a setting. Implemented action: Implement an approved multi-location or recoverable regional design with tested failover and data reconciliation. Recovery objectives should drive resilient data placement, backups, and executable failover procedures.
Incorrect Answers
A:A late stale update cannot replace a newer approved customer record. This addresses a different situation: A reporting table is updated from multiple partners, and records arriving days late overwrite newer authoritative versions. The current scenario instead calls for the more directly applicable verification result: A planned regional outage test restores processing and meets documented recovery objectives. The reason is that recovery objectives should drive resilient data placement, backups, and executable failover procedures.
B:Replaying the same business event does not increase recognized revenue a second time. This addresses a different situation: A payments stream retries messages after transient failures, causing duplicate warehouse revenue rows during replay. The current scenario instead calls for the more directly applicable verification result: A planned regional outage test restores processing and meets documented recovery objectives. The reason is that recovery objectives should drive resilient data placement, backups, and executable failover procedures.
C:A failed exchange-rate refresh prevents publication of a misleading monthly revenue result. This addresses a different situation: A Dataform pipeline materializes monthly revenue before its upstream exchange-rate table refresh completes. The current scenario instead calls for the more directly applicable verification result: A planned regional outage test restores processing and meets documented recovery objectives. The reason is that recovery objectives should drive resilient data placement, backups, and executable failover procedures.
Question 144
The data engineering team must correct this issue: A same-day executive dashboard competes with a large nonurgent nightly historical rebuild. Which controlled engineering action is MOST appropriate?
- Model an appropriate BigQuery Editions capacity reservation with planned commitments.
- Protect streaming settlement capacity and schedule noncritical experiments appropriately.
- Use appropriate interactive and batch workload controls with guaranteed critical capacity.
- Use a governed flexible or separate capacity allocation appropriate to the measured burst.
Explanation
Correct Answer
C:Use appropriate interactive and batch workload controls with guaranteed critical capacity. This addresses the specific problem while respecting business and technical constraints. Validate it by checking: The executive query meets its deadline while historic processing completes within its wider window. Job priority and capacity policies should reflect latency sensitivity and business importance.
Incorrect Answers
A:Model an appropriate BigQuery Editions capacity reservation with planned commitments. This addresses a different situation: A platform has steady high-volume SQL demand but is paying unpredictable per-query cost while finance requires capacity budgets. The current scenario instead calls for the more directly applicable engineering action: Use appropriate interactive and batch workload controls with guaranteed critical capacity. The reason is that job priority and capacity policies should reflect latency sensitivity and business importance.
B:Protect streaming settlement capacity and schedule noncritical experiments appropriately. This addresses a different situation: A payment streaming system is operationally critical, but monthly experimentation triggers heavy resource contention and delayed settlement events. The current scenario instead calls for the more directly applicable engineering action: Use appropriate interactive and batch workload controls with guaranteed critical capacity. The reason is that job priority and capacity policies should reflect latency sensitivity and business importance.
D:Use a governed flexible or separate capacity allocation appropriate to the measured burst. This addresses a different situation: A data science team needs occasional huge feature-engineering runs but competes with a permanently reserved reporting workload. The current scenario instead calls for the more directly applicable engineering action: Use appropriate interactive and batch workload controls with guaranteed critical capacity. The reason is that job priority and capacity policies should reflect latency sensitivity and business importance.
Question 145
A Google Cloud architecture review finds: A retail database migration captures historical tables but fails to process updates made after the initial snapshot. Which principle BEST explains the underlying data-engineering risk?
- Low-downtime database migration needs ongoing change capture, validation, and controlled application switchover.
- Snapshot backfill and ongoing change-data capture must converge without gaps or double application.
- Staged migration must track initial backfill and incremental deltas using durable cursors or manifests.
- Migration validation needs business-value reconciliation beyond record counts.
Explanation
Correct Answer
B:Snapshot backfill and ongoing change-data capture must converge without gaps or double application. This principle identifies the relevant workload or governance requirement. The engineer should first examine: Inspect source log retention, CDC offsets, snapshot timing, and destination reconciliation. A focused corrective action is: Configure supported Datastream change capture with consistent backfill and lag monitoring.
Incorrect Answers
A:Low-downtime database migration needs ongoing change capture, validation, and controlled application switchover. This addresses a different situation: An enterprise migrates a high-write transactional database to Google Cloud and cannot afford a long source freeze during cutover. The current scenario instead calls for the more directly applicable principle: Snapshot backfill and ongoing change-data capture must converge without gaps or double application. The reason is that snapshot backfill and ongoing change-data capture must converge without gaps or double application.
C:Staged migration must track initial backfill and incremental deltas using durable cursors or manifests. This addresses a different situation: A partner shares daily updates while an organization copies older archives into a new Cloud Storage lake. The current scenario instead calls for the more directly applicable principle: Snapshot backfill and ongoing change-data capture must converge without gaps or double application. The reason is that snapshot backfill and ongoing change-data capture must converge without gaps or double application.
D:Migration validation needs business-value reconciliation beyond record counts. This addresses a different situation: A historical financial ledger migration matches table row counts but contains changed decimal precision in several high-value transactions. The current scenario instead calls for the more directly applicable principle: Snapshot backfill and ongoing change-data capture must converge without gaps or double application. The reason is that snapshot backfill and ongoing change-data capture must converge without gaps or double application.
Question 146
A Google Cloud architecture review finds: A marketing dashboard in Looker Studio displays performance summaries but the configured data source grants unrestricted access to restricted BigQuery customer fields. Which principle BEST explains the underlying data-engineering risk?
- Appropriate BI acceleration and precomputation can reduce latency when workloads and limits fit.
- Dynamic masking and column access policies can limit sensitive detail without removing analytical utility.
- Analytical query plans should reduce large intermediates and sort only necessary data.
- BI access must be governed at the data source and warehouse layer, not inferred from dashboard appearance.
Explanation
Correct Answer
D:BI access must be governed at the data source and warehouse layer, not inferred from dashboard appearance. This principle identifies the relevant workload or governance requirement. The engineer should first examine: Inspect connector credentials, BigQuery permissions, selected fields, and report sharing. A focused corrective action is: Use an approved restricted view or authorized dataset with scoped BI credentials.
Incorrect Answers
A:Appropriate BI acceleration and precomputation can reduce latency when workloads and limits fit. This addresses a different situation: A high-traffic operational dashboard executes recurring BigQuery aggregations and users complain about slow interactive response. The current scenario instead calls for the more directly applicable principle: BI access must be governed at the data source and warehouse layer, not inferred from dashboard appearance. The reason is that bI access must be governed at the data source and warehouse layer, not inferred from dashboard appearance.
B:Dynamic masking and column access policies can limit sensitive detail without removing analytical utility. This addresses a different situation: Analysts need aggregate insurance-risk reporting while only authorized reviewers may see exact claimant identifiers. The current scenario instead calls for the more directly applicable principle: BI access must be governed at the data source and warehouse layer, not inferred from dashboard appearance. The reason is that bI access must be governed at the data source and warehouse layer, not inferred from dashboard appearance.
C:Analytical query plans should reduce large intermediates and sort only necessary data. This addresses a different situation: An analytics query sorts a multi-terabyte table globally before returning 20 leaderboard entries, exhausting resources. The current scenario instead calls for the more directly applicable principle: BI access must be governed at the data source and warehouse layer, not inferred from dashboard appearance. The reason is that bI access must be governed at the data source and warehouse layer, not inferred from dashboard appearance.
Question 147
The data engineering team must correct this issue: Three applications produce events into a common stream, and one deploys a breaking field rename without notifying downstream consumers. Which controlled engineering action is MOST appropriate?
- Design elastic ingestion and partitioned analytical storage with stable governed interfaces.
- Register curated assets in an approved catalog with owners, business definitions, and lineage.
- Enforce registry or versioned schema compatibility checks before deploying producer changes.
- Separate portable transformation logic from provider-specific orchestration and version the deployment configuration.
Explanation
Correct Answer
C:Enforce registry or versioned schema compatibility checks before deploying producer changes. This addresses the specific problem while respecting business and technical constraints. Validate it by checking: A breaking event schema is rejected before downstream processors begin failing. Shared data contracts need compatible evolution rules and consumer validation.
Incorrect Answers
A:Design elastic ingestion and partitioned analytical storage with stable governed interfaces. This addresses a different situation: A pilot warehouse handles thousands of daily events but must support hundreds of millions without rewriting every consuming dashboard. The current scenario instead calls for the more directly applicable engineering action: Enforce registry or versioned schema compatibility checks before deploying producer changes. The reason is that shared data contracts need compatible evolution rules and consumer validation.
B:Register curated assets in an approved catalog with owners, business definitions, and lineage. This addresses a different situation: Business teams cannot identify which dataset is authoritative for customer retention because copies lack ownership and lineage. The current scenario instead calls for the more directly applicable engineering action: Enforce registry or versioned schema compatibility checks before deploying producer changes. The reason is that shared data contracts need compatible evolution rules and consumer validation.
D:Separate portable transformation logic from provider-specific orchestration and version the deployment configuration. This addresses a different situation: A data platform expects future multi-cloud processing, but its transformation logic is buried in manual console operations with no versioned definitions. The current scenario instead calls for the more directly applicable engineering action: Enforce registry or versioned schema compatibility checks before deploying producer changes. The reason is that shared data contracts need compatible evolution rules and consumer validation.
Question 148
After applying the change, the team re-examines this condition: An analytics query sorts a multi-terabyte table globally before returning 20 leaderboard entries, exhausting resources. Which result BEST verifies the improvement?
- The top-20 result remains correct while shuffle and sort resource consumption decline.
- A report viewer sees allowed campaign totals but cannot extract protected customer records.
- A sampled date reconciles clicks and orders without multiplication across hourly rows.
- A malicious test filter is treated as data rather than executing unintended SQL.
Explanation
Correct Answer
A:The top-20 result remains correct while shuffle and sort resource consumption decline. This measures the intended corrected behavior rather than only confirming a setting. Implemented action: Restructure the aggregation and limit after appropriate grouping with efficient filtering. Analytical query plans should reduce large intermediates and sort only necessary data.
Incorrect Answers
B:A report viewer sees allowed campaign totals but cannot extract protected customer records. This addresses a different situation: A marketing dashboard in Looker Studio displays performance summaries but the configured data source grants unrestricted access to restricted BigQuery customer fields. The current scenario instead calls for the more directly applicable verification result: The top-20 result remains correct while shuffle and sort resource consumption decline. The reason is that analytical query plans should reduce large intermediates and sort only necessary data.
C:A sampled date reconciles clicks and orders without multiplication across hourly rows. This addresses a different situation: A sales dashboard adds hourly clicks to daily orders with a join on date only, producing inflated conversion rates. The current scenario instead calls for the more directly applicable verification result: The top-20 result remains correct while shuffle and sort resource consumption decline. The reason is that analytical query plans should reduce large intermediates and sort only necessary data.
D:A malicious test filter is treated as data rather than executing unintended SQL. This addresses a different situation: A dashboard generates dynamic SQL by concatenating raw user text into filters and risks malformed or unsafe queries. The current scenario instead calls for the more directly applicable verification result: The top-20 result remains correct while shuffle and sort resource consumption decline. The reason is that analytical query plans should reduce large intermediates and sort only necessary data.
Question 149
After applying the change, the team re-examines this condition: An automated Dataform transform completes, but one critical assertion reports failed rows and no team is notified. Which result BEST verifies the improvement?
- The same input query produces correct output without repeating the resource failure.
- A seeded invalid row triggers an owned alert before the affected dataset is published.
- One failed sample run can be traced from source receipt to the failing transformation.
- A controlled burst stays within approved limits or backs off without dropping records.
Explanation
Correct Answer
B:A seeded invalid row triggers an owned alert before the affected dataset is published. This measures the intended corrected behavior rather than only confirming a setting. Implemented action: Configure monitored assertions that block certification and alert accountable data owners. Data quality assertions require operational ownership and alert routing to prevent incorrect downstream trust.
Incorrect Answers
A:The same input query produces correct output without repeating the resource failure. This addresses a different situation: A large BigQuery query fails with resources-exceeded errors and the operator sees only a generic dashboard red indicator. The current scenario instead calls for the more directly applicable verification result: A seeded invalid row triggers an owned alert before the affected dataset is published. The reason is that data quality assertions require operational ownership and alert routing to prevent incorrect downstream trust.
C:One failed sample run can be traced from source receipt to the failing transformation. This addresses a different situation: A daily pipeline fails across multiple microservices, but logs cannot connect the initial import to the final BigQuery job. The current scenario instead calls for the more directly applicable verification result: A seeded invalid row triggers an owned alert before the affected dataset is published. The reason is that data quality assertions require operational ownership and alert routing to prevent incorrect downstream trust.
D:A controlled burst stays within approved limits or backs off without dropping records. This addresses a different situation: A burst exceeds Pub/Sub publisher limits and clients receive quota errors, but operations mistake the issue for subscriber crashes. The current scenario instead calls for the more directly applicable verification result: A seeded invalid row triggers an owned alert before the affected dataset is published. The reason is that data quality assertions require operational ownership and alert routing to prevent incorrect downstream trust.
Question 150
Before modifying the data platform, the team observes: A team builds new SQL models in a development workspace but schedules them against production datasets using the same credentials. Which evidence should the engineer examine FIRST?
- Inspect Dataform repositories, release configurations, workflow invocations, and IAM scopes.
- Inspect task retry settings, API response behavior, business keys, and outbox records.
- Review repository branches, build artifacts, test cases, and environment permissions.
- Inspect scheduled-query owner, credential scope, destination permissions, and alert routing.
Explanation
Correct Answer
A:Inspect Dataform repositories, release configurations, workflow invocations, and IAM scopes. This evidence directly tests the uncertain part of the described system. ELT deployment should separate development compilation from production execution authority. A controlled response is: Configure separate release workflows and narrowly scoped production invocation identities.
Incorrect Answers
B:Inspect task retry settings, API response behavior, business keys, and outbox records. This addresses a different situation: A pipeline triggers an invoice-export API and Airflow retries the task after a timeout, sending the same invoice twice. The current scenario instead calls for the more directly applicable investigation: Inspect Dataform repositories, release configurations, workflow invocations, and IAM scopes. The reason is that eLT deployment should separate development compilation from production execution authority.
C:Review repository branches, build artifacts, test cases, and environment permissions. This addresses a different situation: Developers change Dataflow transform logic directly in production with no version tags or regression tests. The current scenario instead calls for the more directly applicable investigation: Inspect Dataform repositories, release configurations, workflow invocations, and IAM scopes. The reason is that eLT deployment should separate development compilation from production execution authority.
D:Inspect scheduled-query owner, credential scope, destination permissions, and alert routing. This addresses a different situation: A recurring transformation runs under the credentials of a departed analyst and begins failing when the account is disabled. The current scenario instead calls for the more directly applicable investigation: Inspect Dataform repositories, release configurations, workflow invocations, and IAM scopes. The reason is that eLT deployment should separate development compilation from production execution authority.