Google Professional Data Engineer Practice Test 12
Question 110
A Google Cloud architecture review finds: A partner shares daily updates while an organization copies older archives into a new Cloud Storage lake. Which principle BEST explains the underlying data-engineering risk?
- Managed transfer connectors can replace brittle custom extraction when supported and appropriately scoped.
- Low-downtime database migration needs ongoing change capture, validation, and controlled application switchover.
- Migration planning should separate compute portability, durable storage, and dependency compatibility.
- Staged migration must track initial backfill and incremental deltas using durable cursors or manifests.
Explanation
Correct Answer
D:Staged migration must track initial backfill and incremental deltas using durable cursors or manifests. This principle identifies the relevant workload or governance requirement. The engineer should first examine: Inspect source file versions, checksums, arrival timestamps, and ingestion checkpoints. A focused corrective action is: Create a verified backfill manifest and idempotent incremental import with distinct landing paths.
Incorrect Answers
A:Managed transfer connectors can replace brittle custom extraction when supported and appropriately scoped. This addresses a different situation: An analytics team needs managed recurring imports from an approved external business SaaS source into BigQuery. The current scenario instead calls for the more directly applicable principle: Staged migration must track initial backfill and incremental deltas using durable cursors or manifests. The reason is that staged migration must track initial backfill and incremental deltas using durable cursors or manifests.
B: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: Staged migration must track initial backfill and incremental deltas using durable cursors or manifests. The reason is that staged migration must track initial backfill and incremental deltas using durable cursors or manifests.
C:Migration planning should separate compute portability, durable storage, and dependency compatibility. This addresses a different situation: A batch Hadoop estate has custom Spark jobs and HDFS storage tightly coupled to aging servers. The current scenario instead calls for the more directly applicable principle: Staged migration must track initial backfill and incremental deltas using durable cursors or manifests. The reason is that staged migration must track initial backfill and incremental deltas using durable cursors or manifests.
Question 111
A Google Cloud data engineer is addressing: Two companies want to share selected curated BigQuery datasets without copying unrestricted source projects into each tenant. Which TWO complementary actions should the team take? Select TWO answers.
- Review publisher datasets, subscription requirements, usage agreements, and IAM permissions.
- Publish a controlled BigQuery sharing listing and grant only approved subscriber access.
- Audit embedded viewer roles, export permissions, data source privileges, and contracts.
- Inspect SQL aggregation grain, underlying table security, authorized view grants, and customer groups.
- Inspect subscriber relationships, listing permissions, audit events, and data ownership.
Explanation
Correct Answers
A:Review publisher datasets, subscription requirements, usage agreements, and IAM permissions. This is the applicable diagnostic investigation. Its complementary step is: Publish a controlled BigQuery sharing listing and grant only approved subscriber access. Together they address: Governed BigQuery sharing can provide authorized access to publisher datasets through supported sharing models.
B:Publish a controlled BigQuery sharing listing and grant only approved subscriber access. This is the applicable controlled engineering response. Its complementary step is: Review publisher datasets, subscription requirements, usage agreements, and IAM permissions. Together they address: Governed BigQuery sharing can provide authorized access to publisher datasets through supported sharing models.
Incorrect Answers
C:Audit embedded viewer roles, export permissions, data source privileges, and contracts. 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 (Review publisher datasets, subscription requirements, usage agreements, and IAM permissions.) and to implement (Publish a controlled BigQuery sharing listing and grant only approved subscriber access.).
D: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 (Review publisher datasets, subscription requirements, usage agreements, and IAM permissions.) and to implement (Publish a controlled BigQuery sharing listing and grant only approved subscriber access.).
E:Inspect subscriber relationships, listing permissions, audit events, and data ownership. This could be useful for another system: A business data provider wants to revoke a partner's access to an outdated analytics feed without invalidating access for other subscribers. For this situation, the necessary paired decisions are to examine (Review publisher datasets, subscription requirements, usage agreements, and IAM permissions.) and to implement (Publish a controlled BigQuery sharing listing and grant only approved subscriber access.).
Question 112
A Google Cloud architecture review finds: A production ELT workflow pulls arbitrary local workspace changes without approvals, creating nondeterministic table definitions. Which principle BEST explains the underlying data-engineering risk?
- Query cost control starts with bytes processed, filters, and selecting only required columns.
- Backfill workflows need dependency awareness and capacity controls.
- Versioned compilation and scheduled production execution improve repeatability and change control.
- Scheduled workloads need explicit business time zones and calendar semantics.
Explanation
Correct Answer
C:Versioned compilation and scheduled production execution improve repeatability and change control. This principle identifies the relevant workload or governance requirement. The engineer should first examine: Inspect repository branch, compilation version, release configuration, and invocation logs. A focused corrective action is: Use approved Dataform release configurations and workflow schedules bound to reviewed code.
Incorrect Answers
A:Query cost control starts with bytes processed, filters, and selecting only required columns. 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 principle: Versioned compilation and scheduled production execution improve repeatability and change control. The reason is that versioned compilation and scheduled production execution improve repeatability and change control.
B:Backfill workflows need dependency awareness and capacity controls. 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 principle: Versioned compilation and scheduled production execution improve repeatability and change control. The reason is that versioned compilation and scheduled production execution improve repeatability and change control.
D:Scheduled workloads need explicit business time zones and calendar semantics. 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 principle: Versioned compilation and scheduled production execution improve repeatability and change control. The reason is that versioned compilation and scheduled production execution improve repeatability and change control.
Question 113
A Google Cloud architecture review finds: A data science team needs occasional huge feature-engineering runs but competes with a permanently reserved reporting workload. Which principle BEST explains the underlying data-engineering risk?
- Query cost control starts with bytes processed, filters, and selecting only required columns.
- Business-critical data processing should have planned resource isolation and failover controls.
- Job priority and capacity policies should reflect latency sensitivity and business importance.
- Flexible capacity and assignment strategies can isolate occasional bursts without starving core reporting.
Explanation
Correct Answer
D:Flexible capacity and assignment strategies can isolate occasional bursts without starving core reporting. This principle identifies the relevant workload or governance requirement. The engineer should first examine: Review reservation assignments, burst schedule, idle capacity, and job limits. A focused corrective action is: Use a governed flexible or separate capacity allocation appropriate to the measured burst.
Incorrect Answers
A:Query cost control starts with bytes processed, filters, and selecting only required columns. 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 principle: Flexible capacity and assignment strategies can isolate occasional bursts without starving core reporting. The reason is that flexible capacity and assignment strategies can isolate occasional bursts without starving core reporting.
B:Business-critical data processing should have planned resource isolation and failover controls. 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 principle: Flexible capacity and assignment strategies can isolate occasional bursts without starving core reporting. The reason is that flexible capacity and assignment strategies can isolate occasional bursts without starving core reporting.
C:Job priority and capacity policies should reflect latency sensitivity and business importance. This addresses a different situation: A same-day executive dashboard competes with a large nonurgent nightly historical rebuild. The current scenario instead calls for the more directly applicable principle: Flexible capacity and assignment strategies can isolate occasional bursts without starving core reporting. The reason is that flexible capacity and assignment strategies can isolate occasional bursts without starving core reporting.
Question 114
The data engineering team must correct this issue: A product team requires per-customer event ordering but distributes all messages without a stable key and assumes total ordering across workers. Which controlled engineering action is MOST appropriate?
- Implement versioned reference lookups or temporal enrichment with explicit validity periods.
- Use Pub/Sub and an appropriately configured Dataflow stream with an approved low-latency sink.
- Assign a stable entity key and configure supported ordered delivery or downstream sequence reconciliation.
- Adopt versioned landing paths and idempotent manifest processing before transformation.
Explanation
Correct Answer
C:Assign a stable entity key and configure supported ordered delivery or downstream sequence reconciliation. This addresses the specific problem while respecting business and technical constraints. Validate it by checking: A replay preserves required per-customer sequence without claiming global order. Ordering requirements must be explicit, scoped, and supported by the message architecture.
Incorrect Answers
A:Implement versioned reference lookups or temporal enrichment with explicit validity periods. This addresses a different situation: An IoT pipeline joins fast sensor events to slowly changing asset ownership records and occasionally labels readings with obsolete owners. The current scenario instead calls for the more directly applicable engineering action: Assign a stable entity key and configure supported ordered delivery or downstream sequence reconciliation. The reason is that ordering requirements must be explicit, scoped, and supported by the message architecture.
B:Use Pub/Sub and an appropriately configured Dataflow stream with an approved low-latency sink. This addresses a different situation: A payment service must detect suspicious transaction patterns within seconds rather than after overnight aggregation. The current scenario instead calls for the more directly applicable engineering action: Assign a stable entity key and configure supported ordered delivery or downstream sequence reconciliation. The reason is that ordering requirements must be explicit, scoped, and supported by the message architecture.
D:Adopt versioned landing paths and idempotent manifest processing before transformation. 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 engineering action: Assign a stable entity key and configure supported ordered delivery or downstream sequence reconciliation. The reason is that ordering requirements must be explicit, scoped, and supported by the message architecture.
Question 115
After applying the change, the team re-examines this condition: During a marketing campaign, Pub/Sub backlog grows and Dataflow workers remain fixed far below incoming throughput. Which result BEST verifies the improvement?
- A representative batch finishes without executor OOM and maintains correct aggregates.
- A producer event is available to the approved cloud consumer without changing producer behavior.
- The weekly batch completes on schedule while idle compute cost declines.
- Backlog drains after a planned burst and end-to-end latency stays within target.
Explanation
Correct Answer
D:Backlog drains after a planned burst and end-to-end latency stays within target. This measures the intended corrected behavior rather than only confirming a setting. Implemented action: Tune Dataflow worker limits and pipeline stages using measured bottlenecks. Throughput monitoring and correctly configured autoscaling help manage sustained stream backlogs.
Incorrect Answers
A:A representative batch finishes without executor OOM and maintains correct aggregates. This addresses a different situation: A Dataproc Spark batch shuffles terabytes into a handful of very large partitions and regularly runs out of memory. The current scenario instead calls for the more directly applicable verification result: Backlog drains after a planned burst and end-to-end latency stays within target. The reason is that throughput monitoring and correctly configured autoscaling help manage sustained stream backlogs.
B:A producer event is available to the approved cloud consumer without changing producer behavior. This addresses a different situation: A platform has existing Kafka producers and needs to introduce cloud analytics without rewriting every producer immediately. The current scenario instead calls for the more directly applicable verification result: Backlog drains after a planned burst and end-to-end latency stays within target. The reason is that throughput monitoring and correctly configured autoscaling help manage sustained stream backlogs.
C:The weekly batch completes on schedule while idle compute cost declines. This addresses a different situation: A once-weekly Spark transformation uses a permanently running Dataproc cluster that sits idle most of the week. The current scenario instead calls for the more directly applicable verification result: Backlog drains after a planned burst and end-to-end latency stays within target. The reason is that throughput monitoring and correctly configured autoscaling help manage sustained stream backlogs.
Question 116
A Google Cloud data engineer is addressing: A monthly tax report is generated once per period, but architects propose a continuously running expensive streaming engine. Which TWO complementary actions should the team take? Select TWO answers.
- Inspect object names, source timestamps, hash manifests, schemas, and duplicate deliveries.
- Use a scheduled batch processing workflow with timely validated delivery for monthly reporting.
- Review TLS requirements, authenticated endpoints, data classification, and bucket IAM.
- Clarify report deadline, daily source volume, latency expectations, and batch windows.
- Measure event arrival, detection SLA, event-time skew, and availability requirements.
Explanation
Correct Answers
B:Use a scheduled batch processing workflow with timely validated delivery for monthly reporting. This is the applicable controlled engineering response. Its complementary step is: Clarify report deadline, daily source volume, latency expectations, and batch windows. Together they address: Processing mode should reflect data freshness requirements and operating cost.
D:Clarify report deadline, daily source volume, latency expectations, and batch windows. This is the applicable diagnostic investigation. Its complementary step is: Use a scheduled batch processing workflow with timely validated delivery for monthly reporting. Together they address: Processing mode should reflect data freshness requirements and operating cost.
Incorrect Answers
A:Inspect object names, source timestamps, hash manifests, schemas, and duplicate deliveries. This could be useful for another system: Daily vendor deliveries contain multipart files with duplicate names and changing schemas, making ingestion traceability unreliable. For this situation, the necessary paired decisions are to examine (Clarify report deadline, daily source volume, latency expectations, and batch windows.) and to implement (Use a scheduled batch processing workflow with timely validated delivery for monthly reporting.).
C:Review TLS requirements, authenticated endpoints, data classification, and bucket IAM. This could be useful for another system: A partner uploads raw customer records by custom API, but the team has not assessed encryption in transit or destination access. For this situation, the necessary paired decisions are to examine (Clarify report deadline, daily source volume, latency expectations, and batch windows.) and to implement (Use a scheduled batch processing workflow with timely validated delivery for monthly reporting.).
E:Measure event arrival, detection SLA, event-time skew, and availability requirements. This could be useful for another system: A payment service must detect suspicious transaction patterns within seconds rather than after overnight aggregation. For this situation, the necessary paired decisions are to examine (Clarify report deadline, daily source volume, latency expectations, and batch windows.) and to implement (Use a scheduled batch processing workflow with timely validated delivery for monthly reporting.).
Question 117
A Google Cloud architecture review finds: A reporting application repeatedly runs SELECT star against a wide event table and billing spikes even though it needs five fields. Which principle BEST explains the underlying data-engineering risk?
- Storage-class economics include retrieval fees and minimum duration, not only price per stored GB.
- Query cost control starts with bytes processed, filters, and selecting only required columns.
- Elastic batch processing should match provisioned workers to actual parallel workload demand.
- Worker cost optimization must follow actual pipeline parallelism and bottlenecks.
Explanation
Correct Answer
B:Query cost control starts with bytes processed, filters, and selecting only required columns. This principle identifies the relevant workload or governance requirement. The engineer should first examine: Inspect BigQuery job statistics, query projections, filters, and data partitions. A focused corrective action is: Rewrite queries to project required fields and prune partitions with cost monitoring.
Incorrect Answers
A:Storage-class economics include retrieval fees and minimum duration, not only price per stored GB. 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 principle: Query cost control starts with bytes processed, filters, and selecting only required columns. The reason is that query cost control starts with bytes processed, filters, and selecting only required columns.
C:Elastic batch processing should match provisioned workers to actual parallel workload demand. 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 principle: Query cost control starts with bytes processed, filters, and selecting only required columns. The reason is that query cost control starts with bytes processed, filters, and selecting only required columns.
D:Worker cost optimization must follow actual pipeline parallelism and bottlenecks. This addresses a different situation: A Dataflow batch pipeline processes a few large files using hundreds of workers while bottlenecked on one serialized source stage. The current scenario instead calls for the more directly applicable principle: Query cost control starts with bytes processed, filters, and selecting only required columns. The reason is that query cost control starts with bytes processed, filters, and selecting only required columns.
Question 118
After applying the change, the team re-examines this condition: A Spark job writes millions of tiny Parquet objects, causing large listing overhead and poor query performance across the lake. Which result BEST verifies the improvement?
- A deliberately absent daily partition triggers a reliable alert before downstream reporting.
- Unused scratch output expires while legal records and required lineage artifacts remain intact.
- An incompatible JSON change is flagged and does not silently enter certified lake tables.
- A representative lake query improves read performance without losing or duplicating rows.
Explanation
Correct Answer
D:A representative lake query improves read performance without losing or duplicating rows. This measures the intended corrected behavior rather than only confirming a setting. Implemented action: Compact small files into appropriately sized objects with validated partitioning and recovery plans. Lake query performance depends on file sizing, layout, and processing format, not only total bytes.
Incorrect Answers
A:A deliberately absent daily partition triggers a reliable alert before downstream reporting. 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 verification result: A representative lake query improves read performance without losing or duplicating rows. The reason is that lake query performance depends on file sizing, layout, and processing format, not only total bytes.
B:Unused scratch output expires while legal records and required lineage artifacts remain intact. 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 verification result: A representative lake query improves read performance without losing or duplicating rows. The reason is that lake query performance depends on file sizing, layout, and processing format, not only total bytes.
C:An incompatible JSON change is flagged and does not silently enter certified lake tables. 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 verification result: A representative lake query improves read performance without losing or duplicating rows. The reason is that lake query performance depends on file sizing, layout, and processing format, not only total bytes.
Question 119
A Google Cloud architecture review finds: A lakehouse platform keeps Parquet in Cloud Storage but wants managed governance across BigQuery and compatible external engines. Which principle BEST explains the underlying data-engineering risk?
- Partitioning and clustering can reduce eligible BigQuery query scanning when aligned with predicates.
- BigLake can provide managed table access and governance for eligible lake data across processing systems.
- Cloud SQL is a managed relational option for compatible transactional application workloads.
- A managed in-memory cache can reduce repeated reads but must not become the sole durable source of truth.
Explanation
Correct Answer
B:BigLake can provide managed table access and governance for eligible lake data across processing systems. This principle identifies the relevant workload or governance requirement. The engineer should first examine: Review object layout, table format, supported engines, and access-control model. A focused corrective action is: Create supported BigLake tables and verified catalog grants for authorized engines.
Incorrect Answers
A:Partitioning and clustering can reduce eligible BigQuery query scanning when aligned with predicates. This addresses a different situation: A warehouse stores years of events and most reports filter by event date and customer segment, but all queries scan the full table. The current scenario instead calls for the more directly applicable principle: BigLake can provide managed table access and governance for eligible lake data across processing systems. The reason is that bigLake can provide managed table access and governance for eligible lake data across processing systems.
C:Cloud SQL is a managed relational option for compatible transactional application workloads. This addresses a different situation: A small business runs a conventional PostgreSQL order service and needs managed backups and routine high availability without massive global horizontal write scale. The current scenario instead calls for the more directly applicable principle: BigLake can provide managed table access and governance for eligible lake data across processing systems. The reason is that bigLake can provide managed table access and governance for eligible lake data across processing systems.
D:A managed in-memory cache can reduce repeated reads but must not become the sole durable source of truth. This addresses a different situation: An ecommerce service repeatedly looks up the same short-lived inventory recommendations and overwhelms its primary datastore during traffic peaks. The current scenario instead calls for the more directly applicable principle: BigLake can provide managed table access and governance for eligible lake data across processing systems. The reason is that bigLake can provide managed table access and governance for eligible lake data across processing systems.
Question 120
A Google Cloud data engineer is addressing: A burst exceeds Pub/Sub publisher limits and clients receive quota errors, but operations mistake the issue for subscriber crashes. Which TWO complementary actions should the team take? Select TWO answers.
- Review assertion outputs, invocation status, SQL failure details, and notification settings.
- Inspect trace IDs, task run IDs, logging fields, and service timestamps.
- Tune publishing rates or request justified quota changes while preserving delivery semantics.
- Inspect publisher error codes, quota metrics, topic throughput, and project configuration.
- Review billing export, job metadata, service identities, and budget alert configuration.
Explanation
Correct Answers
C:Tune publishing rates or request justified quota changes while preserving delivery semantics. This is the applicable controlled engineering response. Its complementary step is: Inspect publisher error codes, quota metrics, topic throughput, and project configuration. Together they address: Quota errors must be diagnosed at the affected API and resource scope.
D:Inspect publisher error codes, quota metrics, topic throughput, and project configuration. This is the applicable diagnostic investigation. Its complementary step is: Tune publishing rates or request justified quota changes while preserving delivery semantics. Together they address: Quota errors must be diagnosed at the affected API and resource scope.
Incorrect Answers
A:Review assertion outputs, invocation status, SQL failure details, and notification settings. This could be useful for another system: An automated Dataform transform completes, but one critical assertion reports failed rows and no team is notified. For this situation, the necessary paired decisions are to examine (Inspect publisher error codes, quota metrics, topic throughput, and project configuration.) and to implement (Tune publishing rates or request justified quota changes while preserving delivery semantics.).
B:Inspect trace IDs, task run IDs, logging fields, and service timestamps. This could be useful for another system: A daily pipeline fails across multiple microservices, but logs cannot connect the initial import to the final BigQuery job. For this situation, the necessary paired decisions are to examine (Inspect publisher error codes, quota metrics, topic throughput, and project configuration.) and to implement (Tune publishing rates or request justified quota changes while preserving delivery semantics.).
E:Review billing export, job metadata, service identities, and budget alert configuration. This could be useful for another system: An experimental BigQuery job unexpectedly scans petabytes and costs soar overnight with no spending alerts. For this situation, the necessary paired decisions are to examine (Inspect publisher error codes, quota metrics, topic throughput, and project configuration.) and to implement (Tune publishing rates or request justified quota changes while preserving delivery semantics.).