Google Professional Data Engineer Practice Test 31
Question 300
Before modifying the data platform, the team observes: Thousands of store devices publish small events unpredictably, and downstream systems must process them independently without blocking publishers. Which evidence should the engineer examine FIRST?
- Clarify report deadline, daily source volume, latency expectations, and batch windows.
- Inspect source network route, private connectivity options, service endpoints, and authentication.
- Measure arrival rates, message ordering requirements, retention, and subscriber service objectives.
- Inspect Pub/Sub retention settings, expected outage duration, legal retention, and storage cost.
Explanation
Correct Answer
C:Measure arrival rates, message ordering requirements, retention, and subscriber service objectives. This evidence directly tests the uncertain part of the described system. Decoupled messaging can buffer variable event rates and isolate independent consumers. A controlled response is: Use Pub/Sub topics and independently scaled subscriptions with monitored consumers.
Incorrect Answers
A:Clarify report deadline, daily source volume, latency expectations, and batch windows. This addresses a different situation: A monthly tax report is generated once per period, but architects propose a continuously running expensive streaming engine. The current scenario instead calls for the more directly applicable investigation: Measure arrival rates, message ordering requirements, retention, and subscriber service objectives. The reason is that decoupled messaging can buffer variable event rates and isolate independent consumers.
B:Inspect source network route, private connectivity options, service endpoints, and authentication. This addresses a different situation: An internal ERP system sends sensitive database extracts to Google Cloud but security rules prohibit unrestricted internet endpoints. The current scenario instead calls for the more directly applicable investigation: Measure arrival rates, message ordering requirements, retention, and subscriber service objectives. The reason is that decoupled messaging can buffer variable event rates and isolate independent consumers.
D:Inspect Pub/Sub retention settings, expected outage duration, legal retention, and storage cost. This addresses a different situation: A vehicle telemetry stream might need replay after an outage, but source retention expires sooner than the required recovery window. The current scenario instead calls for the more directly applicable investigation: Measure arrival rates, message ordering requirements, retention, and subscriber service objectives. The reason is that decoupled messaging can buffer variable event rates and isolate independent consumers.
Question 301
The data engineering team must correct this issue: Researchers place thousands of raw objects in a data lake and cannot identify schemas, ownership, or classification. Which controlled engineering action is MOST appropriate?
- Add governed quality checks and curate validated table formats while retaining raw provenance.
- Implement per-source completeness checks with actionable missing-partition alerts.
- Register lake assets in Dataplex Catalog with curated metadata and governed discovery.
- Create a tagged lifecycle policy for transient processing artifacts with documented exclusions.
Explanation
Correct Answer
C:Register lake assets in Dataplex Catalog with curated metadata and governed discovery. This addresses the specific problem while respecting business and technical constraints. Validate it by checking: An authorized researcher finds the correct lake dataset and understands its ownership and sensitivity. A useful data lake needs catalog metadata and lifecycle governance, not only cheap object storage.
Incorrect Answers
A:Add governed quality checks and curate validated table formats while retaining raw provenance. This addresses a different situation: Multiple departments publish raw JSON to a shared lake with inconsistent field definitions that break downstream reusable tables. The current scenario instead calls for the more directly applicable engineering action: Register lake assets in Dataplex Catalog with curated metadata and governed discovery. The reason is that a useful data lake needs catalog metadata and lifecycle governance, not only cheap object storage.
B:Implement per-source completeness checks with actionable missing-partition alerts. This addresses a different situation: A data lake ingestion job repeatedly misses one daily source partition yet storage dashboards show only total object count. The current scenario instead calls for the more directly applicable engineering action: Register lake assets in Dataplex Catalog with curated metadata and governed discovery. The reason is that a useful data lake needs catalog metadata and lifecycle governance, not only cheap object storage.
D:Create a tagged lifecycle policy for transient processing artifacts with documented exclusions. This addresses a different situation: A lake accumulates experimental intermediate outputs that cost more than final retained datasets and lacks automated expiration. The current scenario instead calls for the more directly applicable engineering action: Register lake assets in Dataplex Catalog with curated metadata and governed discovery. The reason is that a useful data lake needs catalog metadata and lifecycle governance, not only cheap object storage.
Question 302
Before modifying the data platform, the team observes: An Airflow DAG reruns after scheduler recovery and reissues the same external billing update twice. Which evidence should the engineer examine FIRST?
- Inspect repository branch, compilation version, release configuration, and invocation logs.
- Inspect Cloud Scheduler timezone, cron expression, daylight rules, and report SLA.
- Review task retries, execution dates, side effects, and idempotency keys.
- Examine task graph, partition completeness, retries, and downstream data freshness.
Explanation
Correct Answer
C:Review task retries, execution dates, side effects, and idempotency keys. This evidence directly tests the uncertain part of the described system. Repeatable orchestration requires idempotent tasks and known checkpoints. A controlled response is: Design tasks with stable run identifiers and safe retries or external deduplication.
Incorrect Answers
A:Inspect repository branch, compilation version, release configuration, and invocation logs. This addresses a different situation: A production ELT workflow pulls arbitrary local workspace changes without approvals, creating nondeterministic table definitions. The current scenario instead calls for the more directly applicable investigation: Review task retries, execution dates, side effects, and idempotency keys. The reason is that repeatable orchestration requires idempotent tasks and known checkpoints.
B:Inspect Cloud Scheduler timezone, cron expression, daylight rules, and report SLA. This addresses a different situation: A daily report must run at 08:00 business time, but the scheduler is configured in UTC and shifts unexpectedly after regional daylight changes. The current scenario instead calls for the more directly applicable investigation: Review task retries, execution dates, side effects, and idempotency keys. The reason is that repeatable orchestration requires idempotent tasks and known checkpoints.
D:Examine task graph, partition completeness, retries, and downstream data freshness. This addresses a different situation: A yearly backfill invokes all daily dependent tasks concurrently, while downstream aggregation assumes every day is already complete. The current scenario instead calls for the more directly applicable investigation: Review task retries, execution dates, side effects, and idempotency keys. The reason is that repeatable orchestration requires idempotent tasks and known checkpoints.
Question 303
A Google Cloud data engineer is addressing: A business data provider wants to revoke a partner's access to an outdated analytics feed without invalidating access for other subscribers. Which TWO complementary actions should the team take? Select TWO answers.
- Revoke only the affected subscriber grant and publish versioned replacement guidance.
- Inspect subscriber relationships, listing permissions, audit events, and data ownership.
- Review publisher datasets, subscription requirements, usage agreements, and IAM permissions.
- Restrict report export and underlying dataset grants consistent with approved aggregate-only access.
- Inspect SQL aggregation grain, underlying table security, authorized view grants, and customer groups.
Explanation
Correct Answers
A:Revoke only the affected subscriber grant and publish versioned replacement guidance. This is the applicable controlled engineering response. Its complementary step is: Inspect subscriber relationships, listing permissions, audit events, and data ownership. Together they address: Sharing products need subscriber-level lifecycle management and accountable permissions.
B:Inspect subscriber relationships, listing permissions, audit events, and data ownership. This is the applicable diagnostic investigation. Its complementary step is: Revoke only the affected subscriber grant and publish versioned replacement guidance. Together they address: Sharing products need subscriber-level lifecycle management and accountable permissions.
Incorrect Answers
C:Review publisher datasets, subscription requirements, usage agreements, and IAM permissions. This could be useful for another system: Two companies want to share selected curated BigQuery datasets without copying unrestricted source projects into each tenant. For this situation, the necessary paired decisions are to examine (Inspect subscriber relationships, listing permissions, audit events, and data ownership.) and to implement (Revoke only the affected subscriber grant and publish versioned replacement guidance.).
D:Restrict report export and underlying dataset grants consistent with approved aggregate-only access. This could be useful for another system: An embedded dashboard lets viewers export all underlying data even though contracts permit only monthly aggregates. For this situation, the necessary paired decisions are to examine (Inspect subscriber relationships, listing permissions, audit events, and data ownership.) and to implement (Revoke only the affected subscriber grant and publish versioned replacement guidance.).
E:Inspect SQL aggregation grain, underlying table security, authorized view grants, and customer groups. This could be useful for another system: A service provider exposes aggregate service quality metrics to customers but must not reveal individual employee work records. For this situation, the necessary paired decisions are to examine (Inspect subscriber relationships, listing permissions, audit events, and data ownership.) and to implement (Revoke only the affected subscriber grant and publish versioned replacement guidance.).
Question 304
The data engineering team must correct this issue: A stream's reported job state stays Running while the actual consumer watermark stops moving for twenty minutes. Which controlled engineering action is MOST appropriate?
- Propagate stable pipeline-run identifiers through logs, jobs, and metrics.
- Refactor the identified heavy stage or adjust supported capacity after explaining the bottleneck.
- Alert on sustained lack of event-time progress and remediate the blocking stage.
- Tune publishing rates or request justified quota changes while preserving delivery semantics.
Explanation
Correct Answer
C:Alert on sustained lack of event-time progress and remediate the blocking stage. This addresses the specific problem while respecting business and technical constraints. Validate it by checking: A test stalled watermark triggers an actionable alert even though the job remains Running. Pipeline health must include progress, latency, and backlog indicators beyond process liveness.
Incorrect Answers
A:Propagate stable pipeline-run identifiers through logs, jobs, and metrics. 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 engineering action: Alert on sustained lack of event-time progress and remediate the blocking stage. The reason is that pipeline health must include progress, latency, and backlog indicators beyond process liveness.
B:Refactor the identified heavy stage or adjust supported capacity after explaining the bottleneck. 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 engineering action: Alert on sustained lack of event-time progress and remediate the blocking stage. The reason is that pipeline health must include progress, latency, and backlog indicators beyond process liveness.
D:Tune publishing rates or request justified quota changes while preserving delivery semantics. 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 engineering action: Alert on sustained lack of event-time progress and remediate the blocking stage. The reason is that pipeline health must include progress, latency, and backlog indicators beyond process liveness.
Question 305
A Google Cloud architecture review finds: A payment service must detect suspicious transaction patterns within seconds rather than after overnight aggregation. Which principle BEST explains the underlying data-engineering risk?
- Replay and recovery objectives depend on source retention and durable staging choices.
- Decoupled messaging can buffer variable event rates and isolate independent consumers.
- Low-latency operational analytics need a streaming path with bounded end-to-end delay.
- Immutable landing identity and manifest metadata enable replay and operational reconciliation.
Explanation
Correct Answer
C:Low-latency operational analytics need a streaming path with bounded end-to-end delay. This principle identifies the relevant workload or governance requirement. The engineer should first examine: Measure event arrival, detection SLA, event-time skew, and availability requirements. A focused corrective action is: Use Pub/Sub and an appropriately configured Dataflow stream with an approved low-latency sink.
Incorrect Answers
A:Replay and recovery objectives depend on source retention and durable staging choices. This addresses a different situation: A vehicle telemetry stream might need replay after an outage, but source retention expires sooner than the required recovery window. The current scenario instead calls for the more directly applicable principle: Low-latency operational analytics need a streaming path with bounded end-to-end delay. The reason is that low-latency operational analytics need a streaming path with bounded end-to-end delay.
B:Decoupled messaging can buffer variable event rates and isolate independent consumers. This addresses a different situation: Thousands of store devices publish small events unpredictably, and downstream systems must process them independently without blocking publishers. The current scenario instead calls for the more directly applicable principle: Low-latency operational analytics need a streaming path with bounded end-to-end delay. The reason is that low-latency operational analytics need a streaming path with bounded end-to-end delay.
D:Immutable landing identity and manifest metadata enable replay and operational reconciliation. This addresses a different situation: Daily vendor deliveries contain multipart files with duplicate names and changing schemas, making ingestion traceability unreliable. The current scenario instead calls for the more directly applicable principle: Low-latency operational analytics need a streaming path with bounded end-to-end delay. The reason is that low-latency operational analytics need a streaming path with bounded end-to-end delay.
Question 306
Before modifying the data platform, the team observes: A Dataflow batch pipeline processes a few large files using hundreds of workers while bottlenecked on one serialized source stage. Which evidence should the engineer examine FIRST?
- Review reservation assignments, edition capacity, slot utilization, and job priorities.
- Inspect Dataproc CPU usage, YARN metrics, cluster autoscaling settings, and job boundaries.
- Inspect BigQuery job statistics, query projections, filters, and data partitions.
- Inspect per-stage parallelism, worker utilization, input sharding, and elapsed time.
Explanation
Correct Answer
D:Inspect per-stage parallelism, worker utilization, input sharding, and elapsed time. This evidence directly tests the uncertain part of the described system. Worker cost optimization must follow actual pipeline parallelism and bottlenecks. A controlled response is: Right-size workers and improve the serial input bottleneck before increasing capacity.
Incorrect Answers
A:Review reservation assignments, edition capacity, slot utilization, and job priorities. 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 investigation: Inspect per-stage parallelism, worker utilization, input sharding, and elapsed time. The reason is that worker cost optimization must follow actual pipeline parallelism and bottlenecks.
B:Inspect Dataproc CPU usage, YARN metrics, cluster autoscaling settings, and job boundaries. This addresses a different situation: A large Spark cluster remains at peak worker count during long idle stages because autoscaling is disabled. The current scenario instead calls for the more directly applicable investigation: Inspect per-stage parallelism, worker utilization, input sharding, and elapsed time. The reason is that worker cost optimization must follow actual pipeline parallelism and bottlenecks.
C:Inspect BigQuery job statistics, query projections, filters, and data partitions. 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 investigation: Inspect per-stage parallelism, worker utilization, input sharding, and elapsed time. The reason is that worker cost optimization must follow actual pipeline parallelism and bottlenecks.
Question 307
The data engineering team must correct this issue: A Spark job writes millions of tiny Parquet objects, causing large listing overhead and poor query performance across the lake. Which controlled engineering action is MOST appropriate?
- Register lake assets in Dataplex Catalog with curated metadata and governed discovery.
- Implement per-source completeness checks with actionable missing-partition alerts.
- Compact small files into appropriately sized objects with validated partitioning and recovery plans.
- Add governed quality checks and curate validated table formats while retaining raw provenance.
Explanation
Correct Answer
C:Compact small files into appropriately sized objects with validated partitioning and recovery plans. This addresses the specific problem while respecting business and technical constraints. Validate it by checking: A representative lake query improves read performance without losing or duplicating rows. Lake query performance depends on file sizing, layout, and processing format, not only total bytes.
Incorrect Answers
A:Register lake assets in Dataplex Catalog with curated metadata and governed discovery. This addresses a different situation: Researchers place thousands of raw objects in a data lake and cannot identify schemas, ownership, or classification. The current scenario instead calls for the more directly applicable engineering action: Compact small files into appropriately sized objects with validated partitioning and recovery plans. The reason is that lake query performance depends on file sizing, layout, and processing format, not only total bytes.
B:Implement per-source completeness checks with actionable missing-partition alerts. This addresses a different situation: A data lake ingestion job repeatedly misses one daily source partition yet storage dashboards show only total object count. The current scenario instead calls for the more directly applicable engineering action: Compact small files into appropriately sized objects with validated partitioning and recovery plans. The reason is that lake query performance depends on file sizing, layout, and processing format, not only total bytes.
D:Add governed quality checks and curate validated table formats while retaining raw provenance. This addresses a different situation: Multiple departments publish raw JSON to a shared lake with inconsistent field definitions that break downstream reusable tables. The current scenario instead calls for the more directly applicable engineering action: Compact small files into appropriately sized objects with validated partitioning and recovery plans. The reason is that lake query performance depends on file sizing, layout, and processing format, not only total bytes.
Question 308
Before modifying the data platform, the team observes: An application routes financial writes to a stale read replica after primary failure, returning success before records are durably committed. Which evidence should the engineer examine FIRST?
- Inspect affected partitions, ingestion manifests, validation history, and recovery sources.
- Inspect dataset locations, backup/copy capabilities, recovery targets, and permitted residency.
- Review primary and replica roles, consistency modes, transaction commit paths, and failover configuration.
- Inspect source retention, worker state, destination location, regional permissions, and documented steps.
Explanation
Correct Answer
C:Review primary and replica roles, consistency modes, transaction commit paths, and failover configuration. This evidence directly tests the uncertain part of the described system. Failover designs must preserve required write consistency and application connection semantics. A controlled response is: Route writes through the supported transactional primary or managed failover endpoint with retry handling.
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: Review primary and replica roles, consistency modes, transaction commit paths, and failover configuration. The reason is that failover designs must preserve required write consistency and application connection semantics.
B: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: Review primary and replica roles, consistency modes, transaction commit paths, and failover configuration. The reason is that failover designs must preserve required write consistency and application connection semantics.
D:Inspect source retention, worker state, destination location, regional permissions, and documented steps. This addresses a different situation: A critical Pub/Sub-to-warehouse flow has a secondary-region deployment template but no retained state, failover routing, or test exercise. The current scenario instead calls for the more directly applicable investigation: Review primary and replica roles, consistency modes, transaction commit paths, and failover configuration. The reason is that failover designs must preserve required write consistency and application connection semantics.
Question 309
A Google Cloud data engineer is addressing: A reporting team creates a materialized view but expects it to instantaneously reflect every base-table update under all query patterns. Which TWO complementary actions should the team take? Select TWO answers.
- Evaluate BI Engine capacity and query optimization with representative dashboard workloads.
- Define governed revenue measures in an appropriate reusable semantic model or certified view.
- Restructure the aggregation and limit after appropriate grouping with efficient filtering.
- Design an eligible materialized aggregation and define an acceptable freshness contract.
- Inspect view definition, refresh status, source mutation rates, and query execution plans.
Explanation
Correct Answers
D:Design an eligible materialized aggregation and define an acceptable freshness contract. This is the applicable controlled engineering response. Its complementary step is: Inspect view definition, refresh status, source mutation rates, and query execution plans. Together they address: Materialized views have supported eligibility and freshness behavior that must be understood.
E:Inspect view definition, refresh status, source mutation rates, and query execution plans. This is the applicable diagnostic investigation. Its complementary step is: Design an eligible materialized aggregation and define an acceptable freshness contract. Together they address: Materialized views have supported eligibility and freshness behavior that must be understood.
Incorrect Answers
A:Evaluate BI Engine capacity and query optimization with representative dashboard workloads. This could be useful for another system: A high-traffic operational dashboard executes recurring BigQuery aggregations and users complain about slow interactive response. For this situation, the necessary paired decisions are to examine (Inspect view definition, refresh status, source mutation rates, and query execution plans.) and to implement (Design an eligible materialized aggregation and define an acceptable freshness contract.).
B:Define governed revenue measures in an appropriate reusable semantic model or certified view. This could be useful for another system: Two finance dashboards report different net revenue because they define discount treatment separately in handwritten SQL. For this situation, the necessary paired decisions are to examine (Inspect view definition, refresh status, source mutation rates, and query execution plans.) and to implement (Design an eligible materialized aggregation and define an acceptable freshness contract.).
C:Restructure the aggregation and limit after appropriate grouping with efficient filtering. This could be useful for another system: An analytics query sorts a multi-terabyte table globally before returning 20 leaderboard entries, exhausting resources. For this situation, the necessary paired decisions are to examine (Inspect view definition, refresh status, source mutation rates, and query execution plans.) and to implement (Design an eligible materialized aggregation and define an acceptable freshness contract.).
Question 310
A Google Cloud data engineer is addressing: A lake accumulates experimental intermediate outputs that cost more than final retained datasets and lacks automated expiration. Which TWO complementary actions should the team take? Select TWO answers.
- Compare source schemas, quality rules, ingestion logs, and rejected rows.
- Inventory object prefixes, formats, source owners, and data classification.
- Create a tagged lifecycle policy for transient processing artifacts with documented exclusions.
- Review bucket usage, object ages, lineage references, recovery requirements, and storage cost.
- Create segregated governed storage or lake access policies with least-privilege permissions.
Explanation
Correct Answers
C:Create a tagged lifecycle policy for transient processing artifacts with documented exclusions. This is the applicable controlled engineering response. Its complementary step is: Review bucket usage, object ages, lineage references, recovery requirements, and storage cost. Together they address: Intermediate-data retention should follow business utility, lineage, and compliance policy.
D:Review bucket usage, object ages, lineage references, recovery requirements, and storage cost. This is the applicable diagnostic investigation. Its complementary step is: Create a tagged lifecycle policy for transient processing artifacts with documented exclusions. Together they address: Intermediate-data retention should follow business utility, lineage, and compliance policy.
Incorrect Answers
A:Compare source schemas, quality rules, ingestion logs, and rejected rows. This could be useful for another system: Multiple departments publish raw JSON to a shared lake with inconsistent field definitions that break downstream reusable tables. For this situation, the necessary paired decisions are to examine (Review bucket usage, object ages, lineage references, recovery requirements, and storage cost.) and to implement (Create a tagged lifecycle policy for transient processing artifacts with documented exclusions.).
B:Inventory object prefixes, formats, source owners, and data classification. This could be useful for another system: Researchers place thousands of raw objects in a data lake and cannot identify schemas, ownership, or classification. For this situation, the necessary paired decisions are to examine (Review bucket usage, object ages, lineage references, recovery requirements, and storage cost.) and to implement (Create a tagged lifecycle policy for transient processing artifacts with documented exclusions.).
E:Create segregated governed storage or lake access policies with least-privilege permissions. This could be useful for another system: A research lake contains both public scientific data and restricted patient samples under one bucket with unrestricted reader roles. For this situation, the necessary paired decisions are to examine (Review bucket usage, object ages, lineage references, recovery requirements, and storage cost.) and to implement (Create a tagged lifecycle policy for transient processing artifacts with documented exclusions.).