PCD Practice Questions 2 — 50 Questions

Question 1

An organization is migrating a 2 TB Oracle database to Cloud SQL for PostgreSQL. They need to minimize downtime and have a limited maintenance window of 30 minutes. Which migration strategy should they use?

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

Accepted Answer

Use DMS with continuous migration (CDC) and promote the replica for cutover.. To migrate a 2 TB Oracle database to Cloud SQL for PostgreSQL with minimal downtime and a 30-minute maintenance window, the best strategy is Database Migration Service (DMS) with continuous migration using change data capture (CDC). DMS performs an initial full load and then continuously replicates ongoing changes, so the cutover can be a quick promotion of the replica, keeping downtime within the window.

Answer

Export the database as a SQL dump and import into Cloud SQL.

Answer

Use BigQuery Data Transfer Service to migrate the data.

Answer

Use a one-time migration job with DMS.

Question 2

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 3

Based on the Cloud Trace exhibit, which service is the primary contributor to the overall request latency?

Accepted Answer

The auth service. The Cloud Trace exhibit shows that the auth service accounts for the largest segment of the overall request latency, as indicated by the longest span duration in the trace waterfall. In Google Cloud Trace, each span represents a service's contribution to the total latency, and the service with the highest cumulative span time is the primary contributor. Since the auth service span is the longest, it is the correct answer.

Answer

The productcatalog service

Answer

The frontend service itself

Answer

The recommendations service

Question 4

A company needs a globally distributed relational database that provides strong ACID transactions across regions and a 99.999% availability SLA. Which Google Cloud database service meets these requirements?

Accepted Answer

Cloud Spanner. Cloud Spanner is the only Google Cloud database that provides a globally distributed, horizontally scalable, relational database with strong ACID transactions and a 99.999% availability SLA. It uses TrueTime and Paxos to synchronize clocks and achieve external consistency across regions. Cloud SQL and AlloyDB are regional and do not offer the same global scale or SLA.

Answer

Cloud SQL

Answer

Cloud Bigtable

Answer

AlloyDB

Question 5

A mobile application developer needs a serverless NoSQL database that supports offline data synchronization across devices and real-time updates. Which Google Cloud database service should they use?

Accepted Answer

Firestore. Firestore is a serverless, NoSQL document database that provides built-in offline data synchronization across devices and real-time updates via snapshot listeners. It automatically handles conflict resolution and data replication, making it ideal for mobile applications that need to work offline and sync when connectivity is restored.

Answer

Cloud Bigtable

Answer

Cloud SQL

Answer

Cloud Spanner

Question 6

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 7

A developer needs to store session state for a user in a cloud-native application. Which storage solution is most appropriate?

Accepted Answer

Memorystore. Memorystore (Redis) is the most appropriate solution for storing session state in a cloud-native application because it provides an in-memory data store with sub-millisecond latency, which is critical for fast session reads and writes. Session state is ephemeral, key-value data that requires high throughput and low latency, and Memorystore supports features like TTL (time-to-live) for automatic session expiration and persistence options for durability. This aligns with the cloud-native principle of stateless application tiers offloading state to a managed caching layer.

Answer

Cloud SQL

Answer

Cloud Storage

Answer

Bigtable

Question 8

Drag and drop the steps to set up a Cloud Build trigger for continuous deployment in the correct order.

Accepted Answer

1. Connect your repository (e.g., GitHub, Cloud Source Repositories). 2. Create a new trigger in Cloud Build. 3. Configure the trigger event (e.g., push to a specific branch). 4. Specify the build configuration file (e.g., cloudbuild.yaml).. A Cloud Build trigger is set up by connecting a repository and configuring the conditions for automatic builds.

Answer

1. Create a new trigger in Cloud Build. 2. Connect your repository. 3. Configure the trigger event. 4. Specify the build configuration file.

Answer

1. Configure the trigger event. 2. Connect your repository. 3. Create a new trigger in Cloud Build. 4. Specify the build configuration file.

Answer

1. Specify the build configuration file. 2. Connect your repository. 3. Create a new trigger in Cloud Build. 4. Configure the trigger event.

Question 9

You are deploying a Cassandra database on GKE. Which resource type should you use to ensure stable network identities and persistent storage per pod?

Accepted Answer

StatefulSet with volumeClaimTemplates. StatefulSet is the correct resource because it provides stable, unique network identities (via headless Service and ordinal pod names) and persistent storage per pod through volumeClaimTemplates, which dynamically create PersistentVolumeClaims for each replica. This is essential for Cassandra, which requires stable node identities and dedicated storage to maintain cluster state and data consistency.

Answer

Job with persistent disk

Answer

Deployment with persistent volume claims

Answer

DaemonSet with hostPath volumes

Question 10

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 11

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 12

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 13

A company runs a batch job that processes large files from Cloud Storage every night. The job must complete within a 2-hour window. If the job fails, it should retry automatically. Which Google Cloud service should they use to orchestrate this job?

Accepted Answer

Cloud Composer. Cloud Composer (D) is the correct choice because it is a fully managed workflow orchestration service built on Apache Airflow, designed to schedule, monitor, and retry batch jobs with complex dependencies. It can trigger a Cloud Storage file processing job, enforce a 2-hour execution window, and automatically retry on failure using Airflow's built-in retry mechanisms and SLA monitoring.

Answer

Compute Engine with startup script

Answer

Cloud Run

Answer

App Engine Cron

Question 14

A company is designing a real-time leaderboard for a mobile gaming application. The leaderboard must support millions of concurrent users updating their scores and querying rankings with low latency (under 100ms). Scores change frequently and require strong consistency for reads. The development team is evaluating Cloud SQL and Cloud Spanner. They estimate they need to handle 100,000 writes per second. Which database should they choose and why?

Accepted Answer

Cloud Spanner because it provides horizontal scaling, strong consistency, and high write throughput.. Cloud Spanner is the correct choice because it provides horizontal scaling with strong consistency and can handle 100,000 writes per second while maintaining ACID transactions and low-latency reads. Unlike Cloud SQL, Spanner scales horizontally across nodes without sacrificing consistency, making it ideal for a real-time leaderboard with millions of concurrent users.

Answer

Cloud Firestore because it offers real-time synchronization and is serverless.

Answer

Cloud Bigtable because it's optimized for high write throughput and time-series data.

Answer

Cloud SQL with read replicas because it's cost-effective and supports ACID transactions.

Question 15

A developer needs to connect a Cloud SQL MySQL instance from an application running on Compute Engine without whitelisting IP addresses. Which method should they use?

Accepted Answer

Configure the application to use Cloud SQL Auth Proxy.. Cloud SQL Auth Proxy provides secure, IAM-authenticated connectivity to a Cloud SQL instance without requiring authorized networks (IP whitelisting) or manual SSL certificate management. The proxy runs locally (or as a sidecar) and establishes an encrypted tunnel to the instance, so the application connects to localhost and the proxy handles authentication and encryption. This directly satisfies the requirement of connecting without whitelisting IP addresses.

Answer

Connect via Cloud Shell using the mysql client.

Answer

Set up a Cloud SQL private IP connection.

Answer

Use SSL/TLS connection with the public IP address.

Question 16

Match each Firebase feature to its description.

Accepted Answer

Cloud Firestore: A NoSQL document database for storing and syncing data in real time.. Firebase features include Cloud Firestore (NoSQL database), Authentication (user login), and Cloud Functions (backend code). Common confusions: mixing NoSQL vs relational, and hosting vs functions.

Answer

Cloud Firestore: A relational database with SQL queries for structured data.

Answer

Firebase Hosting: A Firebase feature for running backend code in response to events.

Question 17

A company is migrating an on-premises PostgreSQL database to Cloud SQL for PostgreSQL. They need to minimize downtime and ensure continuous replication during the cutover. Which Google Cloud service should they use to achieve continuous change data capture (CDC)?

Accepted Answer

Database Migration Service (DMS). Database Migration Service (DMS) supports continuous change data capture (CDC) for PostgreSQL migrations to Cloud SQL by using PostgreSQL's native logical replication. This allows DMS to replicate ongoing changes from the source to the target with minimal downtime, enabling a near-zero-downtime cutover by simply promoting the Cloud SQL instance as the new primary.

Answer

Cloud Data Fusion

Answer

Dataproc

Answer

Cloud Memorystore

Question 18

A company needs a globally distributed, strongly consistent relational database with horizontal scaling and a 99.999% SLA for a financial application. Which Google Cloud database should they choose?

Accepted Answer

Cloud Spanner. Cloud Spanner is the correct choice because it provides a globally distributed, strongly consistent relational database with horizontal scaling and a 99.999% SLA. It combines the benefits of relational database structure (ACID transactions and SQL queries) with horizontal scalability across regions, making it ideal for financial applications that require strict consistency and high availability.

Answer

Cloud SQL

Answer

Cloud Bigtable

Answer

Firestore

Question 19

Which Google Cloud database service is designed as a fully managed, in-memory data store for caching, session management, and pub/sub messaging?

Accepted Answer

Memorystore. Memorystore is Google Cloud's fully managed in-memory data store service, offering Redis and Memcached engines. It is designed for caching, session management, and pub/sub messaging (Redis supports pub/sub), making it the correct match for the described use case.

Answer

Cloud SQL

Answer

Firestore

Answer

Bigtable

Question 20

Which service provides serverless change data capture (CDC) from MySQL and PostgreSQL to BigQuery or Cloud Storage without writing code?

Accepted Answer

Datastream. Datastream is Google Cloud's serverless change data capture (CDC) service that replicates data from MySQL, PostgreSQL, Oracle, and SQL Server into BigQuery or Cloud Storage with minimal configuration and no code. It reads the source database's transaction logs (binlog for MySQL, WAL for PostgreSQL) and streams changes continuously. This matches the question's requirement exactly.

Answer

BigQuery Data Transfer Service

Answer

Cloud Functions

Answer

Dataflow