PCD Practice Test 4 — 25 Questions

Question 1

A team is migrating a Teradata data warehouse to BigQuery using the BigQuery Data Transfer Service. They need to schedule regular incremental transfers. What is the correct configuration for the transfer?

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

Accepted Answer

Create a transfer config with source type 'Teradata', target dataset, and schedule frequency.. BigQuery Data Transfer Service for Teradata supports scheduled transfers. The correct setup is to configure a transfer config with a schedule (e.g., daily) and specify the dataset and table mappings. The service handles incremental loads based on a watermark column.

Answer

Export Teradata data to Cloud Storage and use BigQuery load jobs scheduled via Cloud Scheduler.

Answer

Use Cloud Data Fusion to create a batch pipeline from Teradata to BigQuery.

Answer

Use a BigQuery scheduled query to SELECT * FROM Teradata via federated query.

Question 2

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 3

An e-commerce platform uses Cloud Spanner for transactions and Cloud Bigtable for session state and recommendations. They want to synchronize customer profile changes from Spanner to Bigtable in near real-time. Which three components should they use? (Choose 3)

Accepted Answer

Cloud Spanner change streams. Spanner change streams capture changes, Pub/Sub provides a scalable messaging channel, and Dataflow can transform and write to Bigtable. Cloud Functions could be used but are less suitable for high-throughput. Cloud Scheduler is batch-oriented.

Answer

Cloud Functions

Answer

Cloud Scheduler

Question 4

A team is deploying a microservice application on Google Kubernetes Engine (GKE). They want to ensure high availability and minimize downtime during rolling updates. Which TWO actions should they take? (Choose two.)

Accepted Answer

Configure pod disruption budgets to limit the number of pods that can be unavailable simultaneously.. PodDisruptionBudgets (PDBs) allow you to specify the minimum number of pods that must remain available during voluntary disruptions like rolling updates, ensuring high availability. Option D is correct because readiness probes control when a pod is added to a Service's endpoints; during rolling updates, they prevent traffic from being sent to a pod until it is ready, minimizing downtime.

Answer

Use Horizontal Pod Autoscaler to automatically adjust the number of pods based on CPU utilization.

Answer

Enable liveness probes to automatically restart pods that become unresponsive.

Answer

Enable node auto-repair to automatically replace unhealthy nodes.

Question 5

Your organization uses Cloud Functions (1st gen) to process events from Cloud Storage. Recently, you migrated to Cloud Functions (2nd gen) to take advantage of longer timeouts and concurrency. After the migration, some invocations fail with 'DeadlineExceeded' errors even though the total execution time is below the 60-minute limit. What is the most likely cause?

Accepted Answer

The function is processing multiple concurrent requests per instance, causing a single request to exceed the HTTP timeout due to contention. Cloud Functions (2nd gen) supports concurrent request processing per instance. When multiple requests are handled simultaneously by the same instance, they share the instance's resources, including the HTTP timeout. If one request consumes excessive time due to contention (e.g., waiting for CPU or I/O), other concurrent requests may hit the HTTP request timeout (default 60 minutes for 2nd gen) even if their individual execution time is shorter. This is a common issue when migrating from 1st gen (which processes one request at a time) to 2nd gen with concurrency enabled.

Answer

The function does not have enough memory allocated for the new workload

Answer

The function is being cold-started more frequently due to reduced min instances

Answer

The function timeout is still set to the 1st gen default of 9 minutes

Question 6

A startup is building a social media application with a global user base. They need a database that can handle millions of concurrent users, provide strong consistency, and scale horizontally. They expect high write throughput and need to run complex SQL queries. Which database is most suitable?

Accepted Answer

Cloud Spanner. Cloud Spanner is the only GCP database that provides horizontal scaling, strong consistency, and SQL capabilities for high write throughput globally.

Answer

Cloud Bigtable

Answer

Firestore

Answer

AlloyDB

Question 7

A company runs a stateful application on Compute Engine instances with persistent disks. The application must be highly available and be able to recover from a zonal failure with minimal data loss. The current architecture uses a single instance in one zone. Which design should the team implement?

Accepted Answer

Use a regional persistent disk attached to a managed instance group across two zones.. A regional persistent disk synchronously replicates data across two zones, and when attached to a managed instance group (MIG) spanning those zones, it provides automatic failover with minimal data loss. This design ensures that if one zone fails, the MIG can detach the disk from the failed instance and attach it to a healthy instance in the surviving zone, preserving state with near-zero RPO.

Answer

Use a standard persistent disk and configure a global load balancer to failover.

Answer

Create a snapshot schedule and restore the snapshot to a new instance in another zone on failure.

Answer

Migrate to Cloud Filestore for shared file storage across zones.

Question 8

A company is using Cloud Build for CI and wants to store build artifacts in Artifact Registry. They want to ensure that only successful builds are promoted to production. What should they do?

Accepted Answer

Use Cloud Build steps that push to Artifact Registry only if all previous steps succeed by using `waitFor` and checking exit codes.. Cloud Build steps run sequentially and only if previous steps succeed by default, so pushing to Artifact Registry only if tests pass. Option A is not sufficient because builds on main can still fail. Option C involves manual intervention. Option D is incorrect as it ignores build status.

Answer

Use Cloud Build to deploy to a staging environment, then manually promote to production.

Answer

Use Cloud Build triggers with a condition that only builds on the main branch are deployed.

Answer

Use Cloud Build with a custom script that pushes regardless of build status.

Question 9

Drag and drop the steps to configure a Cloud CDN with a Cloud Load Balancer in the correct order.

Accepted Answer

Create a Cloud Storage bucket, then create an external HTTP(S) load balancer with the bucket as a backend, then enable Cloud CDN on the backend bucket, then update DNS records to point to the load balancer's IP.. Cloud CDN is enabled on a backend bucket of a load balancer, then DNS is configured.

Answer

Create a Cloud Storage bucket, then enable Cloud CDN on the bucket, then create an external HTTP(S) load balancer with the bucket as a backend, then update DNS records.

Answer

Create an external HTTP(S) load balancer, then create a Cloud Storage bucket, then enable Cloud CDN on the bucket, then update DNS records.

Answer

Enable Cloud CDN on a bucket, then create an external HTTP(S) load balancer, then add the bucket as a backend, then update DNS records.

Question 10

A startup is building a REST API on Cloud Run. They expect unpredictable traffic spikes and want to ensure the service can scale from 0 to many instances automatically. What scaling configuration should they use?

Accepted Answer

Set min instances to 0 and max instances to 1000.. Cloud Run's autoscaling allows min instances to be set to 0, enabling the service to scale down to zero when idle (cost-efficient), and max instances to 1000 to handle unpredictable traffic spikes by scaling out horizontally. This configuration ensures the service can start from zero and automatically add instances up to the maximum limit as demand increases, which is ideal for unpredictable workloads.

Answer

Set max instances to 1 to control costs.

Answer

Use manual scaling with a fixed number of instances.

Answer

Set min instances to 5 and max to 100.

Question 11

A financial services company uses BigQuery for analytics but needs to store transactional data with strong consistency and sub-millisecond latency. They are considering Cloud SQL, Cloud Spanner, Bigtable, Memorystore, and Firestore. Which service meets all requirements?

Accepted Answer

Cloud Spanner. Cloud Spanner is the only Google Cloud service that provides both strong consistency and sub-millisecond latency for transactional workloads. It uses TrueTime for global strong consistency and supports ACID transactions with low latency. Cloud SQL offers strong consistency but cannot achieve sub-millisecond latency at scale due to single-region limits. Bigtable provides low latency but only eventual consistency. Memorystore is a caching layer, not a transactional database. Firestore provides strong consistency but typically does not guarantee sub-millisecond latency for high-throughput transactional data, especially under financial workload requirements.

Answer

Cloud SQL

Answer

Bigtable

Answer

Memorystore

Answer

Firestore

Question 12

A media company wants to serve video content globally with low latency and high throughput. Which Google Cloud service is best suited?

Accepted Answer

Cloud CDN. Cloud CDN leverages Google's global edge cache network to deliver video content from locations closest to end users, minimizing latency and offloading origin servers. It integrates with Cloud Load Balancer and Cloud Storage to provide high-throughput, low-latency streaming without requiring users to manage caching infrastructure.

Answer

Cloud Load Balancer

Answer

Cloud Storage with public bucket

Answer

App Engine

Question 13

A team is deploying a microservice on Cloud Run that requires environment variables with sensitive information, such as database passwords. What is the recommended way to provide these secrets?

Accepted Answer

Use Secret Manager to store the secrets and refer to them in the Cloud Run service.. Secret Manager is Google Cloud's dedicated service for securely storing and managing sensitive data like API keys and database passwords. Cloud Run natively integrates with Secret Manager, allowing you to reference secret versions by name in your service configuration without exposing the secret value in plaintext. This approach ensures secrets are encrypted at rest and in transit, and access can be tightly controlled via IAM permissions.

Answer

Inject them directly in the Cloud Run YAML configuration.

Answer

Embed them in the container image as environment variables.

Answer

Store them in a Cloud Storage bucket and mount as a volume.

Question 14

A Cloud Run service experiences high latency under load. The service is a Node.js Express app that processes requests sequentially due to a global mutex. What is the most effective solution?

Accepted Answer

Remove the mutex and ensure request handling is asynchronous. The root cause is that the global mutex forces sequential processing, negating Node.js's asynchronous event loop. Removing the mutex and ensuring asynchronous request handling (e.g., using async/await or Promises) allows the single-threaded event loop to interleave I/O-bound tasks, dramatically reducing latency under concurrent load. This directly addresses the bottleneck without changing the underlying infrastructure.

Answer

Use Cloud Run for Anthos to handle load

Answer

Increase the number of CPUs per container

Answer

Increase the 'max-instances' setting

Question 15

A company is designing a web application that must scale horizontally to handle variable traffic. Which two practices should they implement to ensure the application is stateless and can scale without issues?

Accepted Answer

Offload session state to the user's browser using encrypted cookies.. To achieve statelessness, session state should either be stored in an external cache (e.g., Memorystore) or offloaded to the client (e.g., using cookies). Sticky sessions tie a client to a specific instance, preventing scaling. Using a database like Cloud SQL for session persistence creates a bottleneck. Regional managed instance groups improve availability but do not directly address statelessness.

Answer

Persist session data in Cloud SQL to ensure durability.

Answer

Deploy the application across multiple regional managed instance groups.

Answer

Use sticky sessions to maintain client affinity.

Question 16

A company is migrating a 2 TB Oracle database to AlloyDB for PostgreSQL using Oracle to PostgreSQL migration tool (Ora2Pg). The migration must have minimal downtime. The team plans to use a two-phase approach: first a full dump, then incremental CDC. However, Ora2Pg does not natively support CDC. How should they achieve near-zero downtime migration?

Accepted Answer

Use Database Migration Service (DMS) with Oracle as source and AlloyDB as destination. Database Migration Service (DMS) supports continuous change data capture (CDC) from Oracle to AlloyDB for PostgreSQL, enabling near-zero downtime migration. Unlike Ora2Pg, which only handles full dump and restore, DMS uses Oracle LogMiner or binary logs to capture incremental changes and apply them to AlloyDB in near real-time, making it the correct choice for a two-phase migration with minimal downtime.

Answer

Use Dataflow to stream Oracle changes from Pub/Sub to AlloyDB

Answer

Use Ora2Pg for the full dump, then manually capture Oracle redo logs and apply them to AlloyDB

Answer

Export Oracle data to CSV, load into AlloyDB, then use a custom script with cron to apply changes

Question 17

A developer wants to deploy a containerized application to Google Kubernetes Engine (GKE) and ensure that new pods are automatically created if an existing pod fails. Which Kubernetes resource should be used?

Accepted Answer

Deployment. A Deployment is the correct Kubernetes resource for ensuring declarative updates and self-healing for stateless applications. It manages a ReplicaSet, which maintains the desired number of pod replicas; if a pod fails, the ReplicaSet controller automatically creates a replacement pod to match the desired state.

Answer

Job

Answer

DaemonSet

Answer

StatefulSet

Question 18

A developer is integrating a legacy on-premises application with Cloud Storage. The application generates files that must be uploaded to a bucket. The developer cannot install any additional software on the on-premises server. Which approach should the developer use?

Accepted Answer

Generate a signed URL and use an HTTP PUT request from the application.. A signed URL allows the application to upload files directly via HTTP PUT without requiring any additional software installation on the on-premises server. The developer only needs to generate a signed URL (using Cloud Storage client libraries or gcloud CLI on another system) and then make a simple HTTP request from the application. Option A is wrong because the gcloud CLI would need to be installed on the server, which violates the constraint. Option C is wrong because Cloud Storage FUSE requires installing a FUSE driver on the server. Option D is wrong because deploying a Cloud Function introduces extra complexity and still requires the application to send requests to the function, which would need additional logic.

Answer

Use the gcloud CLI to copy files to the bucket.

Answer

Mount the bucket using Cloud Storage FUSE.

Answer

Deploy a Cloud Function that accepts file uploads and writes to the bucket.

Question 19

A developer wants to enable IAM database authentication for Cloud SQL for PostgreSQL. Which IAM role must be granted to a user or service account to allow login?

Accepted Answer

Cloud SQL Instance User. Cloud SQL IAM database authentication for PostgreSQL requires the Cloud SQL Instance User role (roles/cloudsql.instanceUser) to be granted to a user or service account. This role allows the principal to log in to the database instance using IAM credentials, while the Cloud SQL Admin, Connect, and Client roles do not grant the specific login privilege needed for IAM-based database authentication.

Answer

Cloud SQL Admin

Answer

Cloud SQL Connect

Answer

Cloud SQL Client

Question 20

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.