PCD Practice Test 34 — 15 Questions

Question 1

You are designing a CI/CD pipeline using Cloud Build. You want to automatically trigger a build when code is pushed to a specific branch in Cloud Source Repositories. What is the correct configuration?

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

Accepted Answer

Create a build trigger in Cloud Build with a regex pattern for the branch name.. Cloud Build natively supports build triggers that can be configured to automatically start a build when code is pushed to a specific branch in Cloud Source Repositories. The trigger uses a regex pattern to match the branch name, and Cloud Build listens for repository push events directly without requiring additional services.

Answer

Create a Cloud Function that invokes Cloud Build via API when a push event occurs.

Answer

Add a build step in cloudbuild.yaml that polls the repository.

Answer

Configure a Cloud Pub/Sub topic to notify Cloud Build on push events.

Question 2

A team is deploying a critical application on Google Kubernetes Engine (GKE) and needs to ensure high availability and disaster recovery. Which THREE actions should they take?

Accepted Answer

Use a regional cluster with control plane replicated across zones.. A regional cluster in GKE replicates the control plane across multiple zones within a region, ensuring that if one zone fails, the control plane remains available. This is essential for high availability and disaster recovery, as it eliminates a single point of failure for cluster management operations.

Answer

Deploy all pods in a single zone for simplicity.

Answer

Use a zonal cluster to reduce costs.

Question 3

A company is running a global application on Cloud Spanner. They notice high write latency on a specific table because a frequently updated row is being accessed by many clients simultaneously. Which design pattern should they implement to distribute writes across multiple nodes and reduce contention?

Accepted Answer

Add a hash suffix to the primary key of the hot row to split it into multiple rows.. Adding a hash suffix to the primary key of the hot row splits the single heavily contended row into multiple logical rows, each with a different primary key. This distributes the write load across multiple Cloud Spanner splits and nodes, reducing lock contention and write latency. Cloud Spanner uses a distributed, synchronous replication architecture where a single row is managed by a single split; splitting the hot row into multiple rows allows parallel writes to different splits.

Answer

Increase the number of nodes in the Cloud Spanner instance.

Answer

Use interleaved tables to co-locate related data.

Answer

Migrate the table to Cloud Bigtable which handles hotspots better.

Question 4

A company uses Cloud SQL for MySQL with automated backups enabled. They want to perform point-in-time recovery (PITR) to recover from an accidental data deletion that occurred 10 minutes ago. What must be configured for PITR to work?

Accepted Answer

Enable automated backups only. Point-in-time recovery (PITR) for Cloud SQL for MySQL is automatically enabled when automated backups are enabled. Binary logging is enabled by default and retains logs for 7 days, which is sufficient for recovering data deleted 10 minutes ago. No additional configuration is required in this scenario.

Answer

Increase the binlog retention period

Answer

Enable the slow query log

Answer

Create a cross-region replica

Question 5

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 6

A development team is deploying a new application on Cloud Run. They anticipate unpredictable traffic patterns and want to minimize cold start latency. They also need to ensure that the application can handle sudden spikes without request drops. Which configuration should they use?

Accepted Answer

Set min-instances to a non-zero value to keep some instances warm, and enable CPU always-on.. Setting min-instances to a non-zero value ensures that Cloud Run always keeps at least that many instances warm, eliminating cold starts for baseline traffic. Enabling CPU always-on prevents the instance's CPU from being throttled to zero when idle, allowing the instance to handle incoming requests immediately without a cold start penalty. This combination minimizes latency for unpredictable traffic and ensures capacity to absorb sudden spikes without dropping requests.

Answer

Use App Engine Standard Environment with automatic scaling.

Answer

Set min-instances to 0 and max-instances to a high number to allow scaling from zero.

Answer

Use Cloud Functions instead of Cloud Run for better cold start performance.

Question 7

A company is migrating an on-premises MySQL OLTP application to Cloud SQL. The application requires 48 vCPU, 312 GB RAM, and 30 TB of storage. Which Cloud SQL edition and tier should they choose?

Accepted Answer

Cloud SQL Enterprise with db-custom-48-307200. The application requires 48 vCPU and 312 GB RAM, and Cloud SQL Enterprise with db-custom-48-307200 provides exactly 48 vCPU and 307200 MB (300 GB) of RAM, which is the closest available tier that meets or exceeds the memory requirement. Cloud SQL Enterprise supports custom machine types with up to 48 vCPU and 307200 MB RAM, while Enterprise Plus offers only predefined 'perf-optimized' tiers that do not match the exact vCPU/RAM combination needed.

Answer

Cloud SQL Enterprise Plus with db-perf-optimized-48-300

Answer

Cloud SQL Enterprise with db-custom-32-204800

Answer

Cloud SQL Enterprise Plus with db-perf-optimized-64-400

Question 8

You are designing a globally distributed ecommerce platform that uses Cloud Spanner for order processing. The platform needs to support high read throughput with low latency for product catalog queries. Which two features should you use? (Choose TWO.)

Accepted Answer

Stale reads with bounded staleness. Stale reads with bounded staleness (Option A) allow Cloud Spanner to serve read requests from any replica within a configurable time window (e.g., up to 15 seconds), avoiding the latency of contacting the leader replica. This dramatically increases read throughput for product catalog queries where near-real-time data is acceptable. Local secondary indexes (Option D) are co-located with the base table data in the same split, enabling efficient, low-latency queries on attributes within a single region without cross-node coordination.

Answer

Global secondary indexes

Answer

Interleaved tables

Answer

Strong reads

Question 9

A company is planning to migrate an on-premises Oracle database to Cloud SQL for PostgreSQL. They want to use Google's Database Migration Service (DMS) for continuous migration with minimal downtime. Which source connectivity method does DMS support for connecting to the Oracle database over the internet?

Accepted Answer

VPC Network Peering to on-premises network via Cloud VPN. Google's Database Migration Service (DMS) supports connecting to an on-premises Oracle database over the internet using a Cloud VPN tunnel. This creates an encrypted connection between the on-premises network and Google Cloud VPC, allowing DMS to reach the source database securely. Cloud SQL Auth Proxy is not used for DMS source connectivity; it is a tool for client applications to connect to Cloud SQL instances.

Answer

Cloud SQL Auth Proxy

Answer

Cloud Interconnect

Answer

Direct connection using Oracle Net Services over public IP with SSL

Question 10

A company needs to synchronise data from an on-premises Oracle database to BigQuery in near real-time. They also need to perform complex transformations on the data before loading into BigQuery. Which two services should they use together? (Choose two.)

Accepted Answer

Datastream. Datastream provides serverless change data capture (CDC) from Oracle databases, enabling near real-time synchronization. Dataflow can consume Datastream output (directly or via Pub/Sub) and perform complex transformations using Apache Beam before writing to BigQuery. Cloud Pub/Sub is not mandatory; Datastream can stream directly to BigQuery or to Dataflow. The correct combination for near real-time sync with complex transformations is Datastream and Dataflow.

Answer

Cloud Pub/Sub

Answer

Cloud Scheduler

Answer

Cloud Functions

Question 11

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.. Cloud Run instances are ephemeral and the local filesystem is not persisted across requests or instance restarts. Writing to local disk for data that must survive beyond a single request will cause data loss when the instance is recycled, which is a fundamental characteristic of serverless container platforms.

Answer

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

Answer

Hardcode port 8080 in the container.

Question 12

A company wants to deploy a stateless web application that needs to handle unpredictable traffic spikes with minimal operational overhead. Which Google Cloud compute service is most cost-effective and operationally simple?

Accepted Answer

Cloud Run. Cloud Run is the most cost-effective and operationally simple choice for a stateless web application with unpredictable traffic spikes because it automatically scales from zero to thousands of containers based on request load, charges only for resources used during request processing (down to 100ms increments), and eliminates infrastructure management. It supports any language or framework via container images, making it ideal for stateless HTTP workloads without the cold-start latency concerns of Cloud Functions or the cluster management overhead of GKE.

Answer

App Engine Standard

Answer

Cloud Functions

Answer

Google Kubernetes Engine (GKE)

Answer

Compute Engine with Managed Instance Group

Question 13

You need a managed database service for a lift-and-shift migration of an on-premises SQL Server 2019 OLTP application with up to 64 TB of data. Which Google Cloud database should you choose?

Accepted Answer

Cloud SQL. Cloud SQL is the correct choice because it supports SQL Server 2019, provides managed database services with up to 64 TB of storage (via the Enterprise Plus tier with 64 TB SSD capacity), and is ideal for lift-and-shift migrations of OLTP workloads without requiring application changes. It offers high availability, automated backups, and compatibility with SQL Server features like T-SQL and linked servers, making it a direct replacement for on-premises SQL Server.

Answer

Cloud Bigtable

Answer

AlloyDB

Answer

Cloud Spanner

Question 14

You are designing a Cloud Bigtable schema for a time-series application that stores metrics from millions of devices. The row key is currently deviceID#timestamp. You want to avoid hotspotting on writes and optimize scan performance for reading all data from a specific device within a time range. Which two row key design strategies should you apply? (Choose 2)

Accepted Answer

Add a salt prefix to the row key (e.g., hash of deviceID). Adding a salt prefix (e.g., a hash of the deviceID) distributes write load across multiple tablet servers, preventing hotspotting on a single node when many devices write concurrently. This ensures that sequential timestamps for the same device are not all written to the same tablet, which would otherwise cause a bottleneck.

Answer

Store data in multiple tables per device

Answer

Use a single column family for all metrics

Answer

Promote the device type to the start of the row key

Question 15

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.. Interleaved tables in Cloud Spanner physically colocate parent and child rows on the same split, reducing cross-node reads and improving join performance. This design is critical for globally distributed applications because it minimizes latency and ensures that related data is stored together for efficient access.

Answer

Store large binary blobs directly in Spanner.

Answer

Define secondary indexes on every column.

Answer

Use monotonically increasing primary keys.