Google Professional Data Engineer Practice Test 13
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.).
Question 121
After applying the change, the team re-examines this condition: Thousands of store devices publish small events unpredictably, and downstream systems must process them independently without blocking publishers. Which result BEST verifies the improvement?
- A simulated burst is buffered and multiple consumers process messages without publisher timeouts.
- A test plaintext or unauthenticated request is rejected and approved ingestion succeeds.
- A replay preserves required per-customer sequence without claiming global order.
- A replayed burst produces anomaly alerts within the specified detection window.
Explanation
Correct Answer
A:A simulated burst is buffered and multiple consumers process messages without publisher timeouts. This measures the intended corrected behavior rather than only confirming a setting. Implemented action: Use Pub/Sub topics and independently scaled subscriptions with monitored consumers. Decoupled messaging can buffer variable event rates and isolate independent consumers.
Incorrect Answers
B:A test plaintext or unauthenticated request is rejected and approved ingestion succeeds. This addresses a different situation: A partner uploads raw customer records by custom API, but the team has not assessed encryption in transit or destination access. The current scenario instead calls for the more directly applicable verification result: A simulated burst is buffered and multiple consumers process messages without publisher timeouts. The reason is that decoupled messaging can buffer variable event rates and isolate independent consumers.
C:A replay preserves required per-customer sequence without claiming global order. This addresses a different situation: A product team requires per-customer event ordering but distributes all messages without a stable key and assumes total ordering across workers. The current scenario instead calls for the more directly applicable verification result: A simulated burst is buffered and multiple consumers process messages without publisher timeouts. The reason is that decoupled messaging can buffer variable event rates and isolate independent consumers.
D:A replayed burst produces anomaly alerts within the specified detection window. 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 verification result: A simulated burst is buffered and multiple consumers process messages without publisher timeouts. The reason is that decoupled messaging can buffer variable event rates and isolate independent consumers.
Question 122
The data engineering team must correct this issue: An enterprise migrates a high-write transactional database to Google Cloud and cannot afford a long source freeze during cutover. Which controlled engineering action is MOST appropriate?
- Run field-level and aggregate reconciliation with tolerances defined by financial owners.
- Evaluate an approved Transfer Appliance or equivalent controlled initial bulk-transfer approach.
- Use a supported Database Migration Service path and a rehearsed switchover with reconciliation.
- Create a verified backfill manifest and idempotent incremental import with distinct landing paths.
Explanation
Correct Answer
C:Use a supported Database Migration Service path and a rehearsed switchover with reconciliation. This addresses the specific problem while respecting business and technical constraints. Validate it by checking: Post-cutover row and transaction checks agree and application downtime meets its objective. Low-downtime database migration needs ongoing change capture, validation, and controlled application switchover.
Incorrect Answers
A:Run field-level and aggregate reconciliation with tolerances defined by financial owners. 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 engineering action: Use a supported Database Migration Service path and a rehearsed switchover with reconciliation. The reason is that low-downtime database migration needs ongoing change capture, validation, and controlled application switchover.
B:Evaluate an approved Transfer Appliance or equivalent controlled initial bulk-transfer approach. This addresses a different situation: A research institute has hundreds of terabytes on isolated storage and cannot upload the first copy within its migration window. The current scenario instead calls for the more directly applicable engineering action: Use a supported Database Migration Service path and a rehearsed switchover with reconciliation. The reason is that low-downtime database migration needs ongoing change capture, validation, and controlled application switchover.
D:Create a verified backfill manifest and idempotent incremental import with distinct landing paths. 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 engineering action: Use a supported Database Migration Service path and a rehearsed switchover with reconciliation. The reason is that low-downtime database migration needs ongoing change capture, validation, and controlled application switchover.
Question 123
The data engineering team must correct this issue: A dashboard generates dynamic SQL by concatenating raw user text into filters and risks malformed or unsafe queries. Which controlled engineering action is MOST appropriate?
- Use validated query parameters with reviewed field allowlists and read-only credentials.
- 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.
Explanation
Correct Answer
A:Use validated query parameters with reviewed field allowlists and read-only credentials. This addresses the specific problem while respecting business and technical constraints. Validate it by checking: A malicious test filter is treated as data rather than executing unintended SQL. BI integrations should use parameterized queries and scoped read-only service identities.
Incorrect Answers
B:Define governed revenue measures in an appropriate reusable semantic model or certified view. This addresses a different situation: Two finance dashboards report different net revenue because they define discount treatment separately in handwritten SQL. The current scenario instead calls for the more directly applicable engineering action: Use validated query parameters with reviewed field allowlists and read-only credentials. The reason is that bI integrations should use parameterized queries and scoped read-only service identities.
C:Restructure the aggregation and limit after appropriate grouping with efficient filtering. 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 engineering action: Use validated query parameters with reviewed field allowlists and read-only credentials. The reason is that bI integrations should use parameterized queries and scoped read-only service identities.
D:Design an eligible materialized aggregation and define an acceptable freshness contract. This addresses a different situation: A reporting team creates a materialized view but expects it to instantaneously reflect every base-table update under all query patterns. The current scenario instead calls for the more directly applicable engineering action: Use validated query parameters with reviewed field allowlists and read-only credentials. The reason is that bI integrations should use parameterized queries and scoped read-only service identities.
Question 124
The data engineering team must correct this issue: A service provider exposes aggregate service quality metrics to customers but must not reveal individual employee work records. Which controlled engineering action is MOST appropriate?
- Apply supported row access policies or governed authorized views with tenant controls.
- Revoke only the affected subscriber grant and publish versioned replacement guidance.
- Publish a reviewed aggregate view with narrowly scoped dataset authorization.
- Restrict report export and underlying dataset grants consistent with approved aggregate-only access.
Explanation
Correct Answer
C:Publish a reviewed aggregate view with narrowly scoped dataset authorization. This addresses the specific problem while respecting business and technical constraints. Validate it by checking: A customer sees only allowed service metrics and cannot read base employee-level rows. Authorized views can expose filtered or aggregated analytical data subject to correct permissions.
Incorrect Answers
A:Apply supported row access policies or governed authorized views with tenant controls. This addresses a different situation: A SaaS analytics platform hosts multiple tenant records in one BigQuery table, and users may see only their organization's rows. The current scenario instead calls for the more directly applicable engineering action: Publish a reviewed aggregate view with narrowly scoped dataset authorization. The reason is that authorized views can expose filtered or aggregated analytical data subject to correct permissions.
B:Revoke only the affected subscriber grant and publish versioned replacement guidance. This addresses a different situation: A business data provider wants to revoke a partner's access to an outdated analytics feed without invalidating access for other subscribers. The current scenario instead calls for the more directly applicable engineering action: Publish a reviewed aggregate view with narrowly scoped dataset authorization. The reason is that authorized views can expose filtered or aggregated analytical data subject to correct permissions.
D:Restrict report export and underlying dataset grants consistent with approved aggregate-only access. This addresses a different situation: An embedded dashboard lets viewers export all underlying data even though contracts permit only monthly aggregates. The current scenario instead calls for the more directly applicable engineering action: Publish a reviewed aggregate view with narrowly scoped dataset authorization. The reason is that authorized views can expose filtered or aggregated analytical data subject to correct permissions.
Question 125
After applying the change, the team re-examines this condition: A stream's reported job state stays Running while the actual consumer watermark stops moving for twenty minutes. Which result BEST verifies the improvement?
- The same input query produces correct output without repeating the resource failure.
- A controlled burst stays within approved limits or backs off without dropping records.
- A seeded large-cost estimate is detected before repeated runaway queries continue.
- A test stalled watermark triggers an actionable alert even though the job remains Running.
Explanation
Correct Answer
D:A test stalled watermark triggers an actionable alert even though the job remains Running. This measures the intended corrected behavior rather than only confirming a setting. Implemented action: Alert on sustained lack of event-time progress and remediate the blocking stage. Pipeline health must include progress, latency, and backlog indicators beyond process liveness.
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 test stalled watermark triggers an actionable alert even though the job remains Running. The reason is that pipeline health must include progress, latency, and backlog indicators beyond process liveness.
B: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 test stalled watermark triggers an actionable alert even though the job remains Running. The reason is that pipeline health must include progress, latency, and backlog indicators beyond process liveness.
C:A seeded large-cost estimate is detected before repeated runaway queries continue. This addresses a different situation: An experimental BigQuery job unexpectedly scans petabytes and costs soar overnight with no spending alerts. The current scenario instead calls for the more directly applicable verification result: A test stalled watermark triggers an actionable alert even though the job remains Running. The reason is that pipeline health must include progress, latency, and backlog indicators beyond process liveness.
Question 126
A Google Cloud architecture review finds: A data team migrates an operational reporting platform without identifying owners of critical reports or their acceptance criteria. Which principle BEST explains the underlying data-engineering risk?
- Snapshot backfill and ongoing change-data capture must converge without gaps or double application.
- Managed transfer connectors can replace brittle custom extraction when supported and appropriately scoped.
- Business migration success requires mapped consumers, dependencies, tests, and sign-off.
- Migration planning should separate compute portability, durable storage, and dependency compatibility.
Explanation
Correct Answer
C:Business migration success requires mapped consumers, dependencies, tests, and sign-off. This principle identifies the relevant workload or governance requirement. The engineer should first examine: Interview dashboard owners and review usage logs, critical deadlines, and data contracts. A focused corrective action is: Create a phased migration plan with report parity checks, accountable owners, and rollback criteria.
Incorrect Answers
A:Snapshot backfill and ongoing change-data capture must converge without gaps or double application. This addresses a different situation: A retail database migration captures historical tables but fails to process updates made after the initial snapshot. The current scenario instead calls for the more directly applicable principle: Business migration success requires mapped consumers, dependencies, tests, and sign-off. The reason is that business migration success requires mapped consumers, dependencies, tests, and sign-off.
B: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: Business migration success requires mapped consumers, dependencies, tests, and sign-off. The reason is that business migration success requires mapped consumers, dependencies, tests, and sign-off.
D: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: Business migration success requires mapped consumers, dependencies, tests, and sign-off. The reason is that business migration success requires mapped consumers, dependencies, tests, and sign-off.
Question 127
A Google Cloud architecture review finds: A content pipeline sends customer free-text support tickets to a generative model for categorization without excluding sensitive identifiers. Which principle BEST explains the underlying data-engineering risk?
- Throughput monitoring and correctly configured autoscaling help manage sustained stream backlogs.
- Job-scoped managed compute can reduce idle cost for intermittent batch workloads.
- Event-driven loading needs a clear object-finalization signal and idempotent run identity.
- AI-assisted enrichment must enforce input governance, data minimization, and output validation.
Explanation
Correct Answer
D:AI-assisted enrichment must enforce input governance, data minimization, and output validation. This principle identifies the relevant workload or governance requirement. The engineer should first examine: Inspect ticket contents, model input logs, privacy policies, and enrichment accuracy. A focused corrective action is: De-identify permitted fields and apply reviewed model categorization with validation and restricted output.
Incorrect Answers
A:Throughput monitoring and correctly configured autoscaling help manage sustained stream backlogs. This addresses a different situation: During a marketing campaign, Pub/Sub backlog grows and Dataflow workers remain fixed far below incoming throughput. The current scenario instead calls for the more directly applicable principle: AI-assisted enrichment must enforce input governance, data minimization, and output validation. The reason is that aI-assisted enrichment must enforce input governance, data minimization, and output validation.
B:Job-scoped managed compute can reduce idle cost for intermittent batch workloads. 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 principle: AI-assisted enrichment must enforce input governance, data minimization, and output validation. The reason is that aI-assisted enrichment must enforce input governance, data minimization, and output validation.
C:Event-driven loading needs a clear object-finalization signal and idempotent run identity. This addresses a different situation: A pipeline should start only after a new approved object lands in a bucket, but currently polls every minute and processes partially copied files. The current scenario instead calls for the more directly applicable principle: AI-assisted enrichment must enforce input governance, data minimization, and output validation. The reason is that aI-assisted enrichment must enforce input governance, data minimization, and output validation.
Question 128
The data engineering team must correct this issue: A partner uploads raw customer records by custom API, but the team has not assessed encryption in transit or destination access. Which controlled engineering action is MOST appropriate?
- Configure appropriate message retention or raw event archival for replay and recovery.
- Introduce bounded concurrency, checkpointed pagination, and exponential backoff with jitter.
- Implement versioned reference lookups or temporal enrichment with explicit validity periods.
- Use authenticated encrypted transfer into an access-controlled storage landing zone.
Explanation
Correct Answer
D:Use authenticated encrypted transfer into an access-controlled storage landing zone. This addresses the specific problem while respecting business and technical constraints. Validate it by checking: A test plaintext or unauthenticated request is rejected and approved ingestion succeeds. Security must cover transport, credentials, and raw landing permissions end to end.
Incorrect Answers
A:Configure appropriate message retention or raw event archival for replay and recovery. 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 engineering action: Use authenticated encrypted transfer into an access-controlled storage landing zone. The reason is that security must cover transport, credentials, and raw landing permissions end to end.
B:Introduce bounded concurrency, checkpointed pagination, and exponential backoff with jitter. This addresses a different situation: A customer-relationship API imposes quotas, but ingestion code launches thousands of concurrent requests during a nightly backfill. The current scenario instead calls for the more directly applicable engineering action: Use authenticated encrypted transfer into an access-controlled storage landing zone. The reason is that security must cover transport, credentials, and raw landing permissions end to end.
C: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: Use authenticated encrypted transfer into an access-controlled storage landing zone. The reason is that security must cover transport, credentials, and raw landing permissions end to end.
Question 129
After applying the change, the team re-examines this condition: A nightly sales feed occasionally omits required currency codes, but the current BigQuery load marks every run successful. Which result BEST verifies the improvement?
- A failed exchange-rate refresh prevents publication of a misleading monthly revenue result.
- A deliberately interrupted order update cannot leave mutually inconsistent committed rows.
- A staged file with missing currency codes is blocked or quarantined before reporting.
- Replaying the same business event does not increase recognized revenue a second time.
Explanation
Correct Answer
C:A staged file with missing currency codes is blocked or quarantined before reporting. This measures the intended corrected behavior rather than only confirming a setting. Implemented action: Add schema and domain-value assertions that quarantine invalid rows and fail critical data-quality gates. Data validation must verify business semantics, not just successful file ingestion.
Incorrect Answers
A: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 staged file with missing currency codes is blocked or quarantined before reporting. The reason is that data validation must verify business semantics, not just successful file ingestion.
B:A deliberately interrupted order update cannot leave mutually inconsistent committed rows. This addresses a different situation: An order service needs multi-row transactional correctness, yet engineers propose independent uncoordinated object writes as the system of record. The current scenario instead calls for the more directly applicable verification result: A staged file with missing currency codes is blocked or quarantined before reporting. The reason is that data validation must verify business semantics, not just successful file ingestion.
D: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 staged file with missing currency codes is blocked or quarantined before reporting. The reason is that data validation must verify business semantics, not just successful file ingestion.
Question 130
A design review evaluates this situation: An analytics query sorts a multi-terabyte table globally before returning 20 leaderboard entries, exhausting resources. Which shortcut should the team MOST specifically avoid?
- Promise all materialized views deliver strictly synchronous updates for every unsupported SQL feature.
- Use LIMIT before grouping to compute a misleading leaderboard from arbitrary input rows.
- Give dashboard filters write privileges so user text can alter underlying tables.
- Hide sensitive chart columns visually and call that sufficient warehouse access control.
Explanation
Correct Answer
B:Use LIMIT before grouping to compute a misleading leaderboard from arbitrary input rows. This is the unsafe shortcut directly relevant to the stated system. A better approach is: Restructure the aggregation and limit after appropriate grouping with efficient filtering. Why: Analytical query plans should reduce large intermediates and sort only necessary data.
Incorrect Answers
A:Promise all materialized views deliver strictly synchronous updates for every unsupported SQL feature. This addresses a different situation: A reporting team creates a materialized view but expects it to instantaneously reflect every base-table update under all query patterns. The current scenario instead calls for the more directly applicable unsafe shortcut: Use LIMIT before grouping to compute a misleading leaderboard from arbitrary input rows. The reason is that analytical query plans should reduce large intermediates and sort only necessary data.
C:Give dashboard filters write privileges so user text can alter underlying tables. 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 unsafe shortcut: Use LIMIT before grouping to compute a misleading leaderboard from arbitrary input rows. The reason is that analytical query plans should reduce large intermediates and sort only necessary data.
D:Hide sensitive chart columns visually and call that sufficient warehouse access control. 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 unsafe shortcut: Use LIMIT before grouping to compute a misleading leaderboard from arbitrary input rows. The reason is that analytical query plans should reduce large intermediates and sort only necessary data.