Google Professional Data Engineer Practice Test 16
Question 150
Before modifying the data platform, the team observes: A team builds new SQL models in a development workspace but schedules them against production datasets using the same credentials. Which evidence should the engineer examine FIRST?
- Inspect Dataform repositories, release configurations, workflow invocations, and IAM scopes.
- Inspect task retry settings, API response behavior, business keys, and outbox records.
- Review repository branches, build artifacts, test cases, and environment permissions.
- Inspect scheduled-query owner, credential scope, destination permissions, and alert routing.
Explanation
Correct Answer
A:Inspect Dataform repositories, release configurations, workflow invocations, and IAM scopes. This evidence directly tests the uncertain part of the described system. ELT deployment should separate development compilation from production execution authority. A controlled response is: Configure separate release workflows and narrowly scoped production invocation identities.
Incorrect Answers
B:Inspect task retry settings, API response behavior, business keys, and outbox records. This addresses a different situation: A pipeline triggers an invoice-export API and Airflow retries the task after a timeout, sending the same invoice twice. The current scenario instead calls for the more directly applicable investigation: Inspect Dataform repositories, release configurations, workflow invocations, and IAM scopes. The reason is that eLT deployment should separate development compilation from production execution authority.
C:Review repository branches, build artifacts, test cases, and environment permissions. This addresses a different situation: Developers change Dataflow transform logic directly in production with no version tags or regression tests. The current scenario instead calls for the more directly applicable investigation: Inspect Dataform repositories, release configurations, workflow invocations, and IAM scopes. The reason is that eLT deployment should separate development compilation from production execution authority.
D:Inspect scheduled-query owner, credential scope, destination permissions, and alert routing. This addresses a different situation: A recurring transformation runs under the credentials of a departed analyst and begins failing when the account is disabled. The current scenario instead calls for the more directly applicable investigation: Inspect Dataform repositories, release configurations, workflow invocations, and IAM scopes. The reason is that eLT deployment should separate development compilation from production execution authority.
Question 151
After applying the change, the team re-examines this condition: A product team requires per-customer event ordering but distributes all messages without a stable key and assumes total ordering across workers. Which result BEST verifies the improvement?
- The complete backfill finishes within the source contract with no sustained throttling.
- A source extract reaches the authorized destination without exposing an unauthenticated public endpoint.
- An authorized recovery replays events from a simulated outage without missing the required interval.
- A replay preserves required per-customer sequence without claiming global order.
Explanation
Correct Answer
D:A replay preserves required per-customer sequence without claiming global order. This measures the intended corrected behavior rather than only confirming a setting. Implemented action: Assign a stable entity key and configure supported ordered delivery or downstream sequence reconciliation. Ordering requirements must be explicit, scoped, and supported by the message architecture.
Incorrect Answers
A:The complete backfill finishes within the source contract with no sustained throttling. 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 verification result: A replay preserves required per-customer sequence without claiming global order. The reason is that ordering requirements must be explicit, scoped, and supported by the message architecture.
B:A source extract reaches the authorized destination without exposing an unauthenticated public endpoint. 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 verification result: A replay preserves required per-customer sequence without claiming global order. The reason is that ordering requirements must be explicit, scoped, and supported by the message architecture.
C:An authorized recovery replays events from a simulated outage without missing the required interval. 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 verification result: A replay preserves required per-customer sequence without claiming global order. The reason is that ordering requirements must be explicit, scoped, and supported by the message architecture.
Question 152
After applying the change, the team re-examines this condition: A media archive changes every object to the coldest storage class even though analysts read recent objects daily. Which result BEST verifies the improvement?
- A simulated batch peak no longer violates the protected interactive dashboard SLO.
- A typical month of reads and storage has a lower total cost without violating access needs.
- A representative batch finishes at comparable speed with fewer wasted worker-hours.
- A representative report returns identical metrics while processing fewer billed bytes.
Explanation
Correct Answer
B:A typical month of reads and storage has a lower total cost without violating access needs. This measures the intended corrected behavior rather than only confirming a setting. Implemented action: Assign storage classes and transitions based on measured access patterns and compliance. Storage-class economics include retrieval fees and minimum duration, not only price per stored GB.
Incorrect Answers
A:A simulated batch peak no longer violates the protected interactive dashboard SLO. 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 verification result: A typical month of reads and storage has a lower total cost without violating access needs. The reason is that storage-class economics include retrieval fees and minimum duration, not only price per stored GB.
C:A representative batch finishes at comparable speed with fewer wasted worker-hours. 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 verification result: A typical month of reads and storage has a lower total cost without violating access needs. The reason is that storage-class economics include retrieval fees and minimum duration, not only price per stored GB.
D:A representative report returns identical metrics while processing fewer billed bytes. 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 verification result: A typical month of reads and storage has a lower total cost without violating access needs. The reason is that storage-class economics include retrieval fees and minimum duration, not only price per stored GB.
Question 153
A Google Cloud architecture review finds: An analytics query sorts a multi-terabyte table globally before returning 20 leaderboard entries, exhausting resources. Which principle BEST explains the underlying data-engineering risk?
- Central semantic definitions can prevent inconsistent business metrics across dashboards.
- Analytical query plans should reduce large intermediates and sort only necessary data.
- Appropriate BI acceleration and precomputation can reduce latency when workloads and limits fit.
- BI integrations should use parameterized queries and scoped read-only service identities.
Explanation
Correct Answer
B:Analytical query plans should reduce large intermediates and sort only necessary data. This principle identifies the relevant workload or governance requirement. The engineer should first examine: Review query execution stages, joins, ORDER BY, LIMIT, and slot usage. A focused corrective action is: Restructure the aggregation and limit after appropriate grouping with efficient filtering.
Incorrect Answers
A:Central semantic definitions can prevent inconsistent business metrics across dashboards. 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 principle: Analytical query plans should reduce large intermediates and sort only necessary data. The reason is that analytical query plans should reduce large intermediates and sort only necessary data.
C:Appropriate BI acceleration and precomputation can reduce latency when workloads and limits fit. This addresses a different situation: A high-traffic operational dashboard executes recurring BigQuery aggregations and users complain about slow interactive response. The current scenario instead calls for the more directly applicable principle: Analytical query plans should reduce large intermediates and sort only necessary data. The reason is that analytical query plans should reduce large intermediates and sort only necessary data.
D:BI integrations should use parameterized queries and scoped read-only service identities. 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 principle: Analytical query plans should reduce large intermediates and sort only necessary data. The reason is that analytical query plans should reduce large intermediates and sort only necessary data.
Question 154
A Google Cloud data engineer is addressing: Customer account tiers change over time but year-old invoices must be reported using the tier effective at the invoice date. Which TWO complementary actions should the team take? Select TWO answers.
- Evaluate a nested repeated line-item representation and write correct UNNEST queries.
- Review source change history, effective timestamps, invoice event times, and model grain.
- Implement an appropriate type-2 dimension or equivalent temporal model with valid-time joins.
- Build an incremental partition-aware load with validated late-change reconciliation.
- Introduce appropriate reservation or workload controls while preserving governance.
Explanation
Correct Answers
B:Review source change history, effective timestamps, invoice event times, and model grain. This is the applicable diagnostic investigation. Its complementary step is: Implement an appropriate type-2 dimension or equivalent temporal model with valid-time joins. Together they address: Historical warehouse analysis may require time-versioned dimension attributes.
C:Implement an appropriate type-2 dimension or equivalent temporal model with valid-time joins. This is the applicable controlled engineering response. Its complementary step is: Review source change history, effective timestamps, invoice event times, and model grain. Together they address: Historical warehouse analysis may require time-versioned dimension attributes.
Incorrect Answers
A:Evaluate a nested repeated line-item representation and write correct UNNEST queries. This could be useful for another system: An events schema contains orders with many line items and analysts often query an order together with its items as one logical document. For this situation, the necessary paired decisions are to examine (Review source change history, effective timestamps, invoice event times, and model grain.) and to implement (Implement an appropriate type-2 dimension or equivalent temporal model with valid-time joins.).
D:Build an incremental partition-aware load with validated late-change reconciliation. This could be useful for another system: A daily fact table receives corrections, but each load recomputes every historical year and causes excessive query cost. For this situation, the necessary paired decisions are to examine (Review source change history, effective timestamps, invoice event times, and model grain.) and to implement (Implement an appropriate type-2 dimension or equivalent temporal model with valid-time joins.).
E:Introduce appropriate reservation or workload controls while preserving governance. This could be useful for another system: Interactive analysts share BigQuery capacity with long overnight transformations, causing unpredictable daytime dashboard latencies. For this situation, the necessary paired decisions are to examine (Review source change history, effective timestamps, invoice event times, and model grain.) and to implement (Implement an appropriate type-2 dimension or equivalent temporal model with valid-time joins.).
Question 155
A Google Cloud architecture review finds: An embedded dashboard lets viewers export all underlying data even though contracts permit only monthly aggregates. Which principle BEST explains the underlying data-engineering risk?
- Row-level security can enforce tenant-scoped access when identity and policy design are correct.
- Authorized views can expose filtered or aggregated analytical data subject to correct permissions.
- Data publication should distinguish certified, governed outputs from exploratory drafts.
- Data sharing controls must cover export and connector capabilities as well as visible charts.
Explanation
Correct Answer
D:Data sharing controls must cover export and connector capabilities as well as visible charts. This principle identifies the relevant workload or governance requirement. The engineer should first examine: Audit embedded viewer roles, export permissions, data source privileges, and contracts. A focused corrective action is: Restrict report export and underlying dataset grants consistent with approved aggregate-only access.
Incorrect Answers
A:Row-level security can enforce tenant-scoped access when identity and policy design are correct. 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 principle: Data sharing controls must cover export and connector capabilities as well as visible charts. The reason is that data sharing controls must cover export and connector capabilities as well as visible charts.
B:Authorized views can expose filtered or aggregated analytical data subject to correct permissions. This addresses a different situation: A service provider exposes aggregate service quality metrics to customers but must not reveal individual employee work records. The current scenario instead calls for the more directly applicable principle: Data sharing controls must cover export and connector capabilities as well as visible charts. The reason is that data sharing controls must cover export and connector capabilities as well as visible charts.
C:Data publication should distinguish certified, governed outputs from exploratory drafts. This addresses a different situation: A finance department publishes unreviewed experiment tables to the company-wide BI directory and consumers treat them as financial statements. The current scenario instead calls for the more directly applicable principle: Data sharing controls must cover export and connector capabilities as well as visible charts. The reason is that data sharing controls must cover export and connector capabilities as well as visible charts.
Question 156
A Google Cloud architecture review finds: An Airflow DAG launches a billing aggregation before its source partition arrives, producing empty reports that appear successful. Which principle BEST explains the underlying data-engineering risk?
- Backfill orchestration needs controlled concurrency and partition-level change coordination.
- Orchestration retries must respect the idempotency of downstream actions.
- Orchestration must gate downstream tasks on verified upstream readiness.
- ELT deployment should separate development compilation from production execution authority.
Explanation
Correct Answer
C:Orchestration must gate downstream tasks on verified upstream readiness. This principle identifies the relevant workload or governance requirement. The engineer should first examine: Inspect DAG tasks, task dependencies, partition sensors, and success criteria. A focused corrective action is: Add supported readiness checks and explicit directed dependencies to the Composer workflow.
Incorrect Answers
A:Backfill orchestration needs controlled concurrency and partition-level change coordination. This addresses a different situation: A historical backfill and regular hourly ingestion overlap on the same BigQuery partitions, creating conflicting writes. The current scenario instead calls for the more directly applicable principle: Orchestration must gate downstream tasks on verified upstream readiness. The reason is that orchestration must gate downstream tasks on verified upstream readiness.
B:Orchestration retries must respect the idempotency of downstream actions. This addresses a different situation: A pipeline triggers an invoice-export API and Airflow retries the task after a timeout, sending the same invoice twice. The current scenario instead calls for the more directly applicable principle: Orchestration must gate downstream tasks on verified upstream readiness. The reason is that orchestration must gate downstream tasks on verified upstream readiness.
D:ELT deployment should separate development compilation from production execution authority. This addresses a different situation: A team builds new SQL models in a development workspace but schedules them against production datasets using the same credentials. The current scenario instead calls for the more directly applicable principle: Orchestration must gate downstream tasks on verified upstream readiness. The reason is that orchestration must gate downstream tasks on verified upstream readiness.
Question 157
A Google Cloud architecture review finds: A small business runs a conventional PostgreSQL order service and needs managed backups and routine high availability without massive global horizontal write scale. Which principle BEST explains the underlying data-engineering risk?
- Partitioning and clustering can reduce eligible BigQuery query scanning when aligned with predicates.
- Cloud SQL is a managed relational option for compatible transactional application workloads.
- Point-in-time recovery depends on supported continuous backups/log retention and tested restoration.
- AlloyDB may suit demanding PostgreSQL-compatible operational workloads when measured capabilities and costs fit.
Explanation
Correct Answer
B:Cloud SQL is a managed relational option for compatible transactional application workloads. This principle identifies the relevant workload or governance requirement. The engineer should first examine: Check engine compatibility, transaction volume, connection patterns, HA needs, and backups. A focused corrective action is: Use a suitable Cloud SQL edition and HA configuration with controlled migrations.
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: Cloud SQL is a managed relational option for compatible transactional application workloads. The reason is that cloud SQL is a managed relational option for compatible transactional application workloads.
C:Point-in-time recovery depends on supported continuous backups/log retention and tested restoration. This addresses a different situation: A PostgreSQL operational service needs to restore state from immediately before a faulty data migration, not merely from the last weekly export. The current scenario instead calls for the more directly applicable principle: Cloud SQL is a managed relational option for compatible transactional application workloads. The reason is that cloud SQL is a managed relational option for compatible transactional application workloads.
D:AlloyDB may suit demanding PostgreSQL-compatible operational workloads when measured capabilities and costs fit. This addresses a different situation: A PostgreSQL-compatible application has intensive operational transactions plus complex analytical queries and wants compatible managed performance options. The current scenario instead calls for the more directly applicable principle: Cloud SQL is a managed relational option for compatible transactional application workloads. The reason is that cloud SQL is a managed relational option for compatible transactional application workloads.
Question 158
Before modifying the data platform, the team observes: A lightweight pipeline calls several managed service APIs in order with retry rules, but the team proposes maintaining an entire Airflow deployment for one request chain. Which evidence should the engineer examine FIRST?
- Inspect task retry settings, API response behavior, business keys, and outbox records.
- Inspect template options, bucket identifiers, worker identities, and region restrictions.
- Inspect steps, retry policy, scheduling needs, and required service APIs.
- Inspect DAG tasks, task dependencies, partition sensors, and success criteria.
Explanation
Correct Answer
C:Inspect steps, retry policy, scheduling needs, and required service APIs. This evidence directly tests the uncertain part of the described system. Orchestration services should be selected according to complexity, operational overhead, and supported integration. A controlled response is: Use a suitable Google Cloud Workflows definition for the small stateful service chain.
Incorrect Answers
A:Inspect task retry settings, API response behavior, business keys, and outbox records. This addresses a different situation: A pipeline triggers an invoice-export API and Airflow retries the task after a timeout, sending the same invoice twice. The current scenario instead calls for the more directly applicable investigation: Inspect steps, retry policy, scheduling needs, and required service APIs. The reason is that orchestration services should be selected according to complexity, operational overhead, and supported integration.
B:Inspect template options, bucket identifiers, worker identities, and region restrictions. This addresses a different situation: The same Dataflow template should run in staging and production but contains hardcoded staging bucket names and service-account references. The current scenario instead calls for the more directly applicable investigation: Inspect steps, retry policy, scheduling needs, and required service APIs. The reason is that orchestration services should be selected according to complexity, operational overhead, and supported integration.
D:Inspect DAG tasks, task dependencies, partition sensors, and success criteria. This addresses a different situation: An Airflow DAG launches a billing aggregation before its source partition arrives, producing empty reports that appear successful. The current scenario instead calls for the more directly applicable investigation: Inspect steps, retry policy, scheduling needs, and required service APIs. The reason is that orchestration services should be selected according to complexity, operational overhead, and supported integration.
Question 159
Before modifying the data platform, the team observes: A retail database migration captures historical tables but fails to process updates made after the initial snapshot. Which evidence should the engineer examine FIRST?
- Compare source and destination schemas, numeric types, checksums, and monetary control totals.
- Inspect source database capabilities, replication lag, schema compatibility, and cutover windows.
- Inspect source log retention, CDC offsets, snapshot timing, and destination reconciliation.
- Review source system connector support, synchronization frequency, credentials, and dataset location.
Explanation
Correct Answer
C:Inspect source log retention, CDC offsets, snapshot timing, and destination reconciliation. This evidence directly tests the uncertain part of the described system. Snapshot backfill and ongoing change-data capture must converge without gaps or double application. A controlled response is: Configure supported Datastream change capture with consistent backfill and lag monitoring.
Incorrect Answers
A:Compare source and destination schemas, numeric types, checksums, and monetary control totals. 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 investigation: Inspect source log retention, CDC offsets, snapshot timing, and destination reconciliation. The reason is that snapshot backfill and ongoing change-data capture must converge without gaps or double application.
B:Inspect source database capabilities, replication lag, schema compatibility, and cutover windows. 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 investigation: Inspect source log retention, CDC offsets, snapshot timing, and destination reconciliation. The reason is that snapshot backfill and ongoing change-data capture must converge without gaps or double application.
D:Review source system connector support, synchronization frequency, credentials, and dataset location. 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 investigation: Inspect source log retention, CDC offsets, snapshot timing, and destination reconciliation. The reason is that snapshot backfill and ongoing change-data capture must converge without gaps or double application.
Question 160
Before modifying the data platform, the team observes: A burst exceeds Pub/Sub publisher limits and clients receive quota errors, but operations mistake the issue for subscriber crashes. Which evidence should the engineer examine FIRST?
- Inspect Dataflow watermark, Pub/Sub backlog, worker logs, and sink write latency.
- Review billing export, job metadata, service identities, and budget alert configuration.
- Review assertion outputs, invocation status, SQL failure details, and notification settings.
- Inspect publisher error codes, quota metrics, topic throughput, and project configuration.
Explanation
Correct Answer
D:Inspect publisher error codes, quota metrics, topic throughput, and project configuration. This evidence directly tests the uncertain part of the described system. Quota errors must be diagnosed at the affected API and resource scope. A controlled response is: Tune publishing rates or request justified quota changes while preserving delivery semantics.
Incorrect Answers
A:Inspect Dataflow watermark, Pub/Sub backlog, worker logs, and sink write latency. This addresses a different situation: A stream's reported job state stays Running while the actual consumer watermark stops moving for twenty minutes. The current scenario instead calls for the more directly applicable investigation: Inspect publisher error codes, quota metrics, topic throughput, and project configuration. The reason is that quota errors must be diagnosed at the affected API and resource scope.
B:Review billing export, job metadata, service identities, and budget alert configuration. 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 investigation: Inspect publisher error codes, quota metrics, topic throughput, and project configuration. The reason is that quota errors must be diagnosed at the affected API and resource scope.
C:Review assertion outputs, invocation status, SQL failure details, and notification settings. This addresses a different situation: An automated Dataform transform completes, but one critical assertion reports failed rows and no team is notified. The current scenario instead calls for the more directly applicable investigation: Inspect publisher error codes, quota metrics, topic throughput, and project configuration. The reason is that quota errors must be diagnosed at the affected API and resource scope.