PCD Practice Test 29 — 15 Questions

Question 1

A company wants to use BigQuery to query data stored in AWS S3 without copying it to Google Cloud. Which Google Cloud feature should they use?

Accepted Answer

BigQuery Omni. BigQuery Omni allows you to run BigQuery queries on data stored in Amazon S3 and Azure Blob Storage without copying the data into Google Cloud. It provides a multi-cloud analytics solution by deploying BigQuery compute in the AWS or Azure region where the data resides, enabling direct querying.

Answer

Cloud Datastream

Answer

Cloud Storage FUSE

Answer

BigQuery transfers

Question 2

An engineering team is designing an AlloyDB cluster for an e-commerce platform. They anticipate variable read traffic and want to automatically add or remove read-only compute capacity based on CPU utilization. Which feature should they enable?

Accepted Answer

Read pool autoscaling. AlloyDB’s read pool autoscaling automatically adjusts the number of read pool instances based on metrics like CPU utilization. Query distribution is built-in, but autoscaling is the specific feature for capacity changes. Instance groups are a Compute Engine concept. Read replicas in Cloud SQL are not automatically scaled.

Answer

Enable query distribution across read pool instances.

Answer

Configure a managed instance group for the read pool.

Answer

Set up Cloud SQL read replicas with cross-region replication.

Question 3

Which THREE practices should be followed when deploying a containerized application to Cloud Run?

Accepted Answer

Avoid writing to the local filesystem for data that must persist across requests.. Option A is correct because Cloud Run instances have an in-memory filesystem that is ephemeral and can be discarded when an instance is stopped or replaced, so any data written locally will not persist across requests or instances. Option D is correct because Cloud Run scales horizontally by creating and destroying instances, so the application must be stateless and store session state in an external service such as Firestore, Memorystore, or Cloud SQL. Option E is correct because Cloud Run provides built-in autoscaling (including scale to zero) that automatically adjusts the number of container instances based on incoming traffic, making it the intended mechanism for handling traffic bursts. Option B is incorrect because the request timeout is not a cold-start mitigation; Cloud Run request timeouts default to 300 seconds and can be configured up to 60 minutes, and cold starts are addressed through minimum instances or startup CPU boost. Option C is incorrect because Cloud Run injects the PORT environment variable and expects the container to listen on that port (default 8080), so the port should be read from $PORT rather than hardcoded.

Answer

Set a maximum request timeout of 10 minutes to avoid cold starts.

Answer

Hardcode port 8080 in the container.

Question 4

A company has a legacy monolithic application running on Compute Engine that is being migrated to microservices on GKE. During the migration, they need to maintain performance monitoring across both environments. The legacy application uses Stackdriver Logging and Monitoring agents (now Ops Agent) and exports logs to Cloud Logging. The new microservices are instrumented with OpenTelemetry for traces and metrics. The team wants a unified view of performance across both environments, including distributed traces from the new services and log-based metrics from the legacy app. They also want to correlate logs and traces for troubleshooting. Which solution should they implement?

Accepted Answer

Use Cloud Monitoring dashboards and ingest OpenTelemetry metrics into Cloud Monitoring, while using Cloud Logging log-based metrics from legacy app.. It provides a unified view by ingesting OpenTelemetry metrics into Cloud Monitoring and using Cloud Logging log-based metrics from the legacy app. Cloud Monitoring supports OpenTelemetry metrics via the OpenTelemetry Protocol (OTLP) and can correlate them with log-based metrics from the legacy app, enabling distributed tracing and log correlation in a single dashboard.

Answer

Keep monitoring separate and use separate dashboards for legacy and new.

Answer

Use a third-party APM tool that supports both environments.

Answer

Rewrite the legacy app to use OpenTelemetry.

Question 5

A developer is writing a Cloud Function that throws an exception when processing invalid input. They want to ensure the function returns an appropriate HTTP error response. What should they do?

Accepted Answer

Return a response with a status code and error message from the function. In Cloud Functions (and serverless platforms like Google Cloud Functions), the function code itself is responsible for constructing and returning an HTTP response, including setting the appropriate status code and error message. Throwing an exception alone does not automatically map to an HTTP error response; the platform will typically return a generic 500 error, which is not appropriate for invalid input (e.g., 400 Bad Request). By explicitly returning a response object with a status code (e.g., 400) and a descriptive error message, the developer ensures the client receives a meaningful and correct HTTP error response.

Answer

Log the error and return a success response

Answer

Use a global error handler in the function framework

Answer

Throw an exception and let the platform handle it automatically

Question 6

A healthcare company is designing a new patient portal on Google Cloud. The portal must be highly available across two regions and provide low-latency access to patient records stored in Cloud Firestore. The application will run on Cloud Run. The team needs to ensure that if one region fails, the application remains available and data is not lost. Which TWO strategies should they implement? (Choose two.)

Accepted Answer

Deploy the Cloud Run service to both regions and use a global external HTTP(S) load balancer with health checks to route traffic.. Deploying Cloud Run in multiple regions with a global load balancer provides high availability and low latency by routing users to the nearest healthy region and failing over automatically. Configuring Firestore in multi-region mode ensures data is replicated across regions, providing durability and availability even if one region fails. Together, these strategies meet the requirements for a highly available, multi-region patient portal.

Answer

Set up Cloud SQL for PostgreSQL with cross-region replicas and migrate patient records from Firestore.

Answer

Enable Cloud Run's multi-region deployment feature to automatically replicate the service across regions.

Answer

Use Cloud Storage buckets with dual-region or multi-region settings to store patient records and serve them directly to the application.

Question 7

Drag and drop the steps to create a Cloud Run service in the correct order.

Accepted Answer

Select container image, then configure service settings, then deploy the service. Creating a Cloud Run service involves selecting the container image and configuring settings before deployment.

Answer

Configure service settings, then select container image, then deploy the service

Answer

Deploy the service, then select container image, then configure service settings

Answer

Select container image, then deploy the service, then configure service settings

Question 8

Drag and drop the steps to grant a service account access to a Cloud Storage bucket in the correct order.

Accepted Answer

Step 1: Add the service account as a principal, Step 2: Select the appropriate role, Step 3: Save the changes.. Granting access to a bucket involves adding the service account as a principal with a role.

Answer

Step 1: Select the appropriate role, Step 2: Add the service account as a principal, Step 3: Save the changes.

Answer

Step 1: Add the service account as a principal, Step 2: Save the changes, Step 3: Select the appropriate role.

Answer

Step 1: Save the changes, Step 2: Add the service account as a principal, Step 3: Select the appropriate role.

Question 9

A global e-commerce platform requires a database that can handle millions of concurrent users, provide strong transactional consistency across regions, and achieve 99.999% availability SLA. Which database is the best fit?

Accepted Answer

Cloud Spanner. Cloud Spanner is the only Google Cloud database that offers global distribution, horizontal scaling, ACID transactions across regions, and a 99.999% SLA.

Answer

Cloud SQL with cross-region replication

Answer

Firestore in Native mode

Answer

Bigtable

Question 10

An organization is using Cloud Spanner for a global application. They need to capture all data changes (inserts, updates, deletes) in a Spanner table and stream them to Pub/Sub for downstream processing. Which feature should they use?

Accepted Answer

Cloud Spanner change streams. Cloud Spanner change streams can capture row-level changes and publish them to Pub/Sub via Dataflow or direct integration.

Answer

Datastream for Spanner

Answer

Cloud Bigtable change data capture

Answer

Cloud SQL publication with pglogical

Question 11

Drag and drop the steps to set up a Cloud Function triggered by a Cloud Storage event in the correct order.

Accepted Answer

Write the Cloud Function code, then Deploy the function with the Cloud Storage bucket as trigger, then Upload a file to the Cloud Storage bucket, then Check the Cloud Function logs to verify execution. Cloud Functions can be triggered by Cloud Storage events; deployment includes specifying the bucket trigger.

Answer

Deploy the function with the Cloud Storage bucket as trigger, then Write the Cloud Function code, then Upload a file to the Cloud Storage bucket, then Check the Cloud Function logs to verify execution

Answer

Upload a file to the Cloud Storage bucket, then Write the Cloud Function code, then Deploy the function with the Cloud Storage bucket as trigger, then Check the Cloud Function logs to verify execution

Answer

Check the Cloud Function logs to verify execution, then Write the Cloud Function code, then Deploy the function with the Cloud Storage bucket as trigger, then Upload a file to the Cloud Storage bucket

Question 12

An organisation needs to run SQL queries across data stored in Cloud SQL MySQL and Cloud Storage (CSV files) without moving the data. They want to use BigQuery as the query engine. Which feature should they use?

Accepted Answer

BigQuery federated queries using external tables. BigQuery federated queries using external tables allow you to query data stored in Cloud SQL and Cloud Storage (CSV files) directly from BigQuery without moving the data. This is achieved by creating an external table definition in BigQuery that references the source, enabling SQL queries across both sources in a single query using BigQuery's query engine.

Answer

Cloud SQL cross-database query

Answer

BigQuery Omni

Answer

BigQuery Data Transfer Service

Question 13

An engineer needs to create a Cloud SQL for PostgreSQL instance with high availability. Which configuration ensures automatic failover in less than 60 seconds if the primary zone fails?

Accepted Answer

Select a regional instance with synchronous standby in a different zone.. A regional Cloud SQL instance provisions a synchronous standby in a different zone within the same region. Because replication is synchronous and the standby is already running, failover is automatic and typically completes in under 60 seconds when the primary zone fails. This is the only Cloud SQL configuration that provides built-in HA with automatic failover.

Answer

Select a zonal instance with a read replica in a different zone.

Answer

Select a zonal instance with automatic storage increase enabled.

Answer

Select a cross-region replica for disaster recovery.

Question 14

You have a Cloud Spanner database with a table that has a secondary index. You notice that queries using the index are performing a back join to the base table. Which index feature can you use to avoid this back join?

Accepted Answer

Use the STORING clause to include the queried columns in the index. In Cloud Spanner, a secondary index does not store all columns of the base table by default. When a query uses the index but needs columns not present in the index, Spanner performs a back join (also called a table lookup) to retrieve those missing columns from the base table. The STORING clause allows you to include additional non-key columns in the index itself, making the index covering and eliminating the need for the back join.

Answer

Use a composite primary key to include those columns

Answer

Use a local secondary index instead of a global one

Answer

Use interleaving with the base table

Question 15

Which TWO Google Cloud services are suitable for deploying serverless applications that scale automatically based on demand?

Accepted Answer

Cloud Functions.. Cloud Functions (option C) is a serverless execution environment that automatically scales instances from zero to thousands in response to event triggers, such as HTTP requests or Cloud Pub/Sub messages, without requiring any infrastructure management. Cloud Run (option E) is a managed compute platform that runs stateless containers in a fully serverless manner, scaling each revision automatically based on incoming request concurrency (up to 80 concurrent requests per container instance by default). Both services abstract away underlying servers and scale to zero when idle, making them ideal for serverless applications.

Answer

Cloud Storage.

Answer

Google Kubernetes Engine.

Answer

Compute Engine with managed instance groups.