PCD Multiple Select — 50 Questions

Question 1

A company is deploying a three-node Bigtable cluster for production. They anticipate growth in read throughput and want to plan for scaling. Which two actions can they take to increase read throughput? (Choose TWO.)

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Add more nodes to the existing cluster. Option A is correct because adding more nodes to a Bigtable cluster increases the cluster's compute capacity, and Bigtable distributes tablet serving across nodes, so additional nodes directly raise the aggregate read throughput available to the cluster. Option E is correct because adding a second cluster in a different zone (a multi-cluster routing setup) lets the application serve reads from multiple clusters, increasing overall read throughput and resilience; with multi-cluster routing, reads can be served from the nearest or all clusters depending on the app profile. Option B is wrong because a development instance is a single-node, non-production, non-HA instance with much lower performance and cannot be scaled for production read throughput. Option C is wrong because HDD storage in Bigtable is cheaper but has higher latency and lower throughput than SSD, so it would not increase read throughput. Option D is wrong because Key Visualizer is a monitoring/diagnostic tool that visualizes access patterns and row-key hot spots; it does not itself increase performance, though it can inform schema or key design changes.

Answer

Switch to a development instance type

Answer

Change storage to HDD

Answer

Use Key Visualizer to increase performance

Question 2

A company wants to migrate an on-premises MySQL database to Cloud SQL with minimal downtime. Which two steps should they take? (Choose two.)

Accepted Answer

Use Database Migration Service to create a continuous replication job. Option A is correct because Database Migration Service (DMS) supports continuous replication from an on-premises MySQL source to Cloud SQL, keeping the target in sync so the cutover can happen with minimal downtime. Option D is correct because DMS continuous replication relies on the source MySQL binary log (binlog) to capture ongoing changes; binary logging must be enabled (with a suitable binlog_format such as ROW) for replication to work. Options B, C, and E are not required: the Cloud SQL Auth Proxy is used by clients to connect securely to Cloud SQL, not on the source database; a full backup/restore is part of the initial snapshot that DMS handles automatically, not a separate required step; and disabling foreign key checks on the source is neither necessary nor advisable for a migration.

Answer

Set up a Cloud SQL proxy on the source database

Answer

Take a full backup and restore it to Cloud SQL before replication

Answer

Disable foreign key checks on the source database

Question 3

An organization is migrating from Oracle to Cloud SQL for PostgreSQL. They need to convert Oracle packages (which use PL/SQL) into PostgreSQL equivalents. Which TWO approaches are correct for handling Oracle packages?

Accepted Answer

Rewrite PL/SQL code into PL/pgSQL syntax.. Option A is correct because Oracle packages contain PL/SQL code, and Cloud SQL for PostgreSQL executes procedural logic in PL/pgSQL, so the package bodies must be manually rewritten into PL/pgSQL syntax (including converting constructs like %TYPE, %ROWTYPE, and Oracle-specific built-ins). Option D is correct because PostgreSQL has no native package object; the standard migration pattern is to map each Oracle package to a dedicated PostgreSQL schema that groups the equivalent functions and procedures, preserving the package's namespace and encapsulation. Option B is wrong because pgAgent is only a job scheduler for PostgreSQL and does not translate or execute Oracle PL/SQL packages. Option C is wrong because PostgreSQL (and Cloud SQL for PostgreSQL) does not provide an Oracle compatibility mode that runs PL/SQL packages natively. Option E is wrong because the Orafce extension supplies Oracle-compatible functions and operators (e.g., NVL, DECODE, TO_DATE behaviors) but does not provide a PL/SQL package engine or convert package code.

Answer

Use pgAgent to schedule package execution.

Answer

Use Oracle compatibility mode in PostgreSQL.

Answer

Install the Orafce extension for Oracle compatibility.

Question 4

A DevOps team is troubleshooting high latency in a Cloud Bigtable instance. They notice that the row keys are lexicographically sorted timestamps. Which TWO actions will MOST improve performance? (Select 2 answers)

Accepted Answer

Use salt (hash prefix) in the row key. Option D is correct because Bigtable stores rows in lexicographic order and distributes them across tablets by key range; timestamp-only keys cause all new writes to land on the last tablet, creating a hotspot, so adding a salt (hash prefix) spreads writes across many tablets and improves throughput/latency. Option E is correct because prepending a high-cardinality field such as user ID before the timestamp also distributes writes across the key space while still allowing efficient prefix scans per user, eliminating the sequential-write hotspot. Option A is not correct because adding nodes increases capacity but cannot fix a hot tablet caused by a monotonically increasing key, since a single tablet cannot be split to parallelize that hotspot. Option B is not correct because more column families do not change row-key distribution and can even add overhead. Option C is not correct because compression reduces storage and some I/O, but it does not address the write hotspot from lexicographically sorted timestamp keys.

Answer

Add more Bigtable nodes

Answer

Increase the number of column families

Answer

Enable compression on column families

Question 5

Which three are valid ways to authenticate a service account when using the Google Cloud client libraries? (Choose three.)

Accepted Answer

Attaching a service account to a Compute Engine instance and letting the metadata server provide credentials.. Options A, B, and D are correct. These are standard methods for Application Default Credentials (ADC). Attaching a service account to a Compute Engine instance allows the metadata server to provide credentials (A). Setting the GOOGLE_APPLICATION_CREDENTIALS environment variable to point to a service account key file is another valid method (B). Using the gcloud CLI default application credentials is also a valid approach (D). Option C is incorrect because OAuth 2.0 client IDs for web applications are used for user authentication, not service account authentication. Option E is incorrect because API keys are not used for service account authentication; they are used for simple API access without a service account.

Answer

Using OAuth 2.0 client IDs for web applications.

Answer

Using an API key in the client library initialization.

Question 6

Which THREE are valid approaches for automating testing in a Cloud Build CI pipeline?

Accepted Answer

Use Cloud Build triggers to run tests on every push to a branch.. Option B is correct because Cloud Build triggers (e.g., a push trigger on a branch) can automatically start a build that executes test steps whenever code is pushed, which is a standard CI testing approach. Option D is correct because Cloud Build supports multiple steps in a build config, and steps run in parallel by default unless you declare waitFor dependencies, so tests can be distributed across parallel steps for faster feedback. Option E is correct because a build step can use a custom builder image (referenced via the 'name' field in cloudbuild.yaml) that contains your test framework and commands, allowing arbitrary test execution inside the pipeline. Option A is not a valid testing approach because Cloud Monitoring is for metrics, dashboards, and alerting, not for shipping or executing test results as part of CI. Option C is not a valid Cloud Build testing approach because Cloud Build does not natively gate steps on manual approval; approvals are handled by external systems or release pipelines, not as a built-in Cloud Build test mechanism.

Answer

Use Cloud Build to ship test results to Cloud Monitoring.

Answer

Use Cloud Build to run tests only after manual approval.

Question 7

A developer wants to automatically detect and capture application errors in a production environment on Google Cloud. Which two Google Cloud services should be enabled? (Choose two.)

Accepted Answer

Cloud Error Reporting. Cloud Error Reporting aggregates and displays application errors in real time, allowing developers to automatically detect and capture errors in production. Cloud Logging stores all application logs, which Error Reporting uses as a source to identify and analyze error events. Together, they provide a complete solution for error detection and capture without manual intervention.

Answer

Cloud Trace

Answer

Cloud Profiler

Answer

Cloud Debugger

Question 8

A company is using Cloud Run for a stateless API. They want to ensure that the service can handle sudden traffic spikes. Which two features should they configure?

Accepted Answer

Enable container concurrency.. Enabling container concurrency allows a single Cloud Run container instance to handle multiple requests simultaneously, up to the configured concurrency limit (default 80, max 1000). This improves throughput and resource utilization during traffic spikes without requiring additional instances. Option D is correct because setting max instances to a high value ensures the service can scale out to handle sudden load by creating more container instances, up to the configured maximum, preventing cold starts and request queuing.

Answer

Use Cloud Load Balancing.

Answer

Enable CPU always on allocation.

Answer

Set min instances to zero to save cost.

Question 9

A company is migrating a 500 GB MySQL database to Cloud SQL for MySQL 8.0. They want to test the migration with minimal risk before the final cutover. Which TWO testing approaches should they use?

Accepted Answer

Set up shadow writes to dual-write to both source and target databases.. Option A is correct because shadow writes (dual-writing to both the source and the Cloud SQL target) let the team validate write-path compatibility, replication fidelity, and application behavior against MySQL 8.0 in production-like conditions without exposing users to the new database, which directly supports low-risk testing before cutover. Option C is correct because running comparison queries on a snapshot of data from both databases verifies data consistency and correctness (row counts, checksums, key business queries) after a test migration, catching transformation or replication discrepancies before the final cutover. Option B is not appropriate because synthetic-data load testing alone does not validate real data fidelity or application compatibility with the actual 500 GB dataset. Option D is not a testing approach for validating the migration; migrating only the schema with Database Migration Service tests connectivity and DDL compatibility but not data movement or application behavior. Option E is a prudent risk-management step, but a rollback plan is not a migration testing approach and does not itself validate the migration.

Answer

Perform load testing using synthetic data only.

Answer

Use Database Migration Service to migrate only the schema first.

Answer

Create a rollback plan before starting migration.

Question 10

Which THREE are best practices for building applications on GKE? (Choose three.)

Accepted Answer

Set resource requests and limits for CPU and memory. Option A is correct because setting CPU and memory requests lets the scheduler place pods on nodes with sufficient capacity, while limits prevent a single container from starving others and enable proper QoS classes and autoscaling decisions. Option C is correct because readiness probes ensure traffic only reaches containers that are ready to serve, and liveness probes let kubelet restart containers that are stuck or deadlocked, improving availability and reliability. Option E is correct because Google-managed SSL certificates integrate with GKE Ingress to automatically provision and renew TLS certificates for HTTPS, reducing operational overhead and avoiding expired-certificate outages. Option B is not a best practice because pinning pods to specific node instances via nodeSelector reduces scheduling flexibility and resilience, and performance consistency is better achieved with node affinity, taints/tolerations, or dedicated node pools. Option D is not a best practice because StatefulSets are intended for stateful workloads needing stable identities and persistent storage, while stateless applications should generally use Deployments for simpler scaling and rolling updates.

Answer

Use nodeSelector to pin pods to specific node instances for performance consistency

Answer

Use StatefulSets for all applications to preserve state across restarts

Question 11

A company is using Cloud Storage to store sensitive customer data. They need to ensure data is encrypted at rest and access is controlled. Which TWO statements are true regarding data protection in Cloud Storage? (Choose two.)

Accepted Answer

By default, data in Cloud Storage is encrypted at rest using Google-managed encryption keys.. Option A is correct because Cloud Storage always encrypts data at rest by default using Google-managed encryption keys (AES-256), requiring no configuration from the customer. Option D is correct because CMEK (Customer-Managed Encryption Keys), backed by Cloud KMS, lets the company generate, rotate, and control the keys protecting its objects, satisfying stricter key-ownership requirements. Option B is wrong because a signed URL only grants time-limited access to an object; it does not revoke or modify the object's ACLs. Option C is wrong because uniform bucket-level access changes how permissions are managed (IAM at the bucket level) and has no effect on encryption at rest, which remains enabled. Option E is wrong because bucket-level IAM policies grant access to principals (users, groups, service accounts) and cannot be scoped to compute instances with specific service accounts.

Answer

Using a signed URL revokes the underlying object's ACL.

Answer

Enabling uniform bucket-level access disables encryption at rest.

Answer

Bucket-level policies can restrict access to only compute instances with specific service accounts.

Question 12

An engineer is designing a disaster recovery plan for a production AlloyDB cluster. The primary cluster is in us-central1. They need a cross-region replica that can be promoted to primary in the event of a regional failure. The replica should also be able to handle read traffic in the secondary region. Which THREE steps should they take? (Choose 3.)

Accepted Answer

Promote the secondary cluster to primary during a disaster.. Option D is correct because AlloyDB cross-region replication is established by creating a secondary cluster in a different region (us-west1) that continuously replicates from the primary cluster in us-central1, which is exactly the foundation of this DR design. Option E is correct because a secondary cluster does not serve reads by default; adding a read pool (read-only instances) to the secondary cluster enables it to handle read traffic in the secondary region as required. Option A is correct because promoting the secondary cluster to primary is the designed failover mechanism that makes it writable and lets it take over production duties during a regional failure. Option B is incorrect because read pools are cluster-level resources, not instance-level, so an 'instance-level read pool' is not a valid AlloyDB construct. Option C is incorrect because AlloyDB Omni is a downloadable, containerized edition for running AlloyDB outside Google Cloud, and it is irrelevant to configuring cross-region replication for a managed AlloyDB cluster.

Answer

Configure an instance-level read pool in the secondary cluster.

Answer

Enable AlloyDB Omni on the secondary cluster.

Question 13

A company is designing a cloud-native application on Google Kubernetes Engine. They want to ensure high availability and scalability for their microservices. Which two best practices should they follow?

Accepted Answer

Use horizontal pod autoscaling based on custom metrics.. Horizontal Pod Autoscaling (HPA) based on custom metrics allows the application to automatically scale the number of pod replicas in response to application-specific signals (e.g., requests per second, queue depth) rather than just CPU/memory. This ensures that each microservice can handle varying load efficiently, maintaining high availability and scalability without over-provisioning.

Answer

Use a single cluster per region.

Answer

Use a single replica for each service to reduce cost.

Answer

Use stateful sets for all services.

Question 14

A company wants to deploy a containerized application to Cloud Run. Which two approaches are supported? (Choose two.)

Accepted Answer

Use gcloud beta run deploy with --source flag to build and deploy from source. Option A is correct because Cloud Run supports source-based deployments via the `gcloud beta run deploy --source` flag, which uses Cloud Build (with buildpacks) to automatically build the container image from source code and deploy it to Cloud Run. Option E is correct because the standard container-based workflow is to build the image locally with Docker, push it to a registry such as Artifact Registry (or Container Registry), and then deploy it using `gcloud run deploy --image` referencing that image. Option B is incorrect because Cloud Functions is a separate serverless product for functions, not a mechanism for packaging and deploying containers to Cloud Run. Option C is incorrect because the Cloud Run console does not accept a Dockerfile for server-side building; builds from source are done via gcloud/Cloud Build, not by uploading a Dockerfile to the console. Option D is incorrect because deploying to Kubernetes Engine (GKE) and then migrating is not a supported Cloud Run deployment approach; Cloud Run deploys containers directly from a registry or source.

Answer

Use Cloud Functions to package the container as a function

Answer

Upload a Dockerfile to Cloud Run console and let it build

Answer

Use Kubernetes Engine to deploy the container and then migrate to Cloud Run

Question 15

A company is deploying a global microservices application on Cloud Run. They need to design for high availability, scalability, and low latency. Which three practices should they implement? (Choose three.)

Accepted Answer

Enable Cloud CDN for caching static assets.. Cloud CDN caches static assets at Google's global edge locations, reducing latency for users worldwide and offloading requests from Cloud Run. This improves performance for static content like images, CSS, and JavaScript, which is essential for a global microservices application requiring low latency.

Answer

Use Cloud Scheduler to trigger services periodically.

Answer

Set a limit on the number of Cloud Run containers per revision to control costs.

Question 16

A team is building a serverless event-driven application using Cloud Functions and Cloud Pub/Sub. The function processes messages from a Pub/Sub subscription and writes results to Firestore. During peak hours, the function experiences high latency and some messages are being retried multiple times. Which three steps should the team take to improve reliability and scalability? (Choose three.)

Accepted Answer

Enable retry policy on the Pub/Sub subscription to automatically retry failed messages.. Enabling a retry policy on the Pub/Sub subscription ensures that messages that fail to be processed (e.g., due to transient errors or timeouts) are automatically retried. This prevents message loss and improves reliability by allowing the Cloud Function to reprocess messages without manual intervention. The retry policy works with the subscription's acknowledgement deadline, so messages are redelivered if not acknowledged in time.

Answer

Batch multiple Pub/Sub messages into a single Cloud Function invocation.

Answer

Increase the Cloud Function timeout to the maximum allowed value.

Question 17

A company uses Cloud Spanner for a globally distributed application. They need to design their table schema for maximum scalability and performance. Which two design considerations are critical? (Choose two.)

Accepted Answer

Use interleaved tables to colocate related data.. Option A is correct because interleaved tables physically colocate child rows with their parent row, so related data is stored on the same node and joins between parent and child can be executed locally without network shuffling, which improves performance and scalability for hierarchical data. Option E is correct because Cloud Spanner shards data by primary key ranges, so choosing keys that spread writes evenly across nodes (for example, using hashed or reversed keys) avoids hotspots and lets the system scale horizontally. Option B is not appropriate because Spanner is optimized for structured relational data and large binary blobs should be stored in Cloud Storage with references in Spanner. Option C is wrong because indexing every column adds write amplification and storage overhead without query benefit. Option D is wrong because monotonically increasing primary keys (such as timestamps or sequential IDs) concentrate writes on the last key range, creating a hotspot that limits scalability.

Answer

Store large binary blobs directly in Spanner.

Answer

Define secondary indexes on every column.

Answer

Use monotonically increasing primary keys.

Question 18

Which TWO statements about Cloud Trace are correct?

Accepted Answer

Trace can be integrated with Cloud Monitoring for alerting. Option A is correct because Cloud Trace integrates with Cloud Monitoring, allowing you to create alerting policies based on trace-derived metrics such as latency distributions and error rates, so you can be notified when performance degrades. Option D is correct because Cloud Trace is specifically designed to collect and correlate spans across distributed services, enabling end-to-end latency analysis of requests as they flow through microservices and other components. Option B is not correct because Trace does not collect latency data from all requests by default; sampling is applied (often 0.1 requests per second per instance plus a percentage of additional requests) unless you configure custom sampling or use the Trace API/SDK to instrument and control what is captured. Option C is not correct because Trace does not automatically create dashboards; visualization of trace data is done in the Trace console, and dashboards are created in Cloud Monitoring, not automatically by Trace. Option E is not correct because auto-scaling based on latency is a function of services like Managed Instance Groups or GKE autoscaling (often using Monitoring metrics), not a capability of Cloud Trace itself.

Answer

Trace collects latency data from all requests by default

Answer

Trace automatically creates dashboards for visualization

Answer

Trace supports auto-scaling based on latency

Question 19

A company deploys a containerized application to Cloud Run using Cloud Build. They want to implement a rolling update strategy with zero downtime. Which two actions should they take? (Choose two.)

Accepted Answer

Gradually shift traffic to the new revision using the gcloud run services update-traffic command.. The `gcloud run services update-traffic` command allows you to gradually shift traffic from the current revision to a new revision, enabling a rolling update with zero downtime. This command supports percentage-based traffic splitting, which ensures that the new revision is incrementally exposed to users while the old revision remains active, thus maintaining service availability throughout the deployment.

Answer

Create a new Cloud Run service for the new revision.

Answer

Set the min-instances attribute to 1 to keep at least one instance running.

Answer

Use the gcloud run deploy command with the --concurrency flag.

Question 20

A team is implementing a CI/CD pipeline for a Cloud Function using Cloud Build. Which three steps should they include in their cloudbuild.yaml? (Choose 3)

Accepted Answer

Static code analysis. Static code analysis (A) is correct because it helps identify code quality issues, security vulnerabilities, and adherence to coding standards early in the pipeline, which is a best practice for Cloud Functions. Running unit tests (C) is essential to validate function logic before deployment. Deploying the function (B) is the final step that pushes the validated code to Cloud Functions, making it a required step in the CI/CD pipeline.

Answer

Build a container image

Answer

Manual approval step