Google PROFESSIONAL-CLOUD-DATABASE-ENGINEER Online Practice Questions and Exam Preparation

Google PROFESSIONAL-CLOUD-DATABASE-ENGINEER Online Questions & Answers

• Question 101:

  You work for a financial services company that wants to use fully managed database services. Traffic volume for your consumer services products has increased annually at a constant rate with occasional spikes around holidays. You frequently need to upgrade the capacity of your database. You want to use Cloud Spanner and include an automated method to increase your hardware capacity to support a higher level of concurrency. What should you do?

  A. Use linear scaling to implement the Autoscaler-based architecture
  B. Use direct scaling to implement the Autoscaler-based architecture.
  C. Upgrade the Cloud Spanner instance on a periodic basis during the scheduled maintenance window.
  D. Set up alerts that are triggered when Cloud Spanner utilization metrics breach the threshold, and then schedule an upgrade during the scheduled maintenance window.
  A. Use linear scaling to implement the Autoscaler-based architecture

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  Explanation/Reference:

  Linear scaling is best used with load patterns that change more gradually or have a few large peaks. The method calculates the minimum number of nodes or processing units required to keep utilization below the scaling threshold. The number of nodes or processing units added or removed in each scaling event is not limited to a fixed step amount. https://cloud.google.com/spanner/docs/autoscaling-overview#linear

• Question 102:

  Your company wants to migrate its MySQL, PostgreSQL, and Microsoft SQL Server on-premises databases to Google Cloud. You need a solution that provides near-zero downtime, requires no application changes, and supports change data

  capture (CDC).

  What should you do?

  A. Use the native export and import functionality of the source database.
  B. Create a database on Google Cloud, and use database links to perform the migration.
  C. Create a database on Google Cloud, and use Dataflow for database migration.
  D. Use Database Migration Service.
  D. Use Database Migration Service.

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  Explanation/Reference:

  Simplify migrations to the cloud. Available now for MySQL and PostgreSQL, with SQL Server and Oracle migrations in preview.

  1.

  Migrate to Cloud SQL and AlloyDB for PostgreSQL from on-premises, Google Cloud, or other clouds

  2.

  Replicate data continuously for minimal downtime migrations

  3.

  Serverless and easy to set up

• Question 103:

  You are designing an augmented reality game for iOS and Android devices. You plan to use Cloud Spanner as the primary backend database for game state storage and player authentication. You want to track in-game rewards that players unlock at every stage of the game. During the testing phase, you discovered that costs are much higher than anticipated, but the query response times are within the SLA. You want to follow Google-recommended practices. You need the database to be performant and highly available while you keep costs low. What should you do?

  A. Manually scale down the number of nodes after the peak period has passed.
  B. Use interleaving to co-locate parent and child rows.
  C. Use the Cloud Spanner query optimizer to determine the most efficient way to execute the SQL query.
  D. Use granular instance sizing in Cloud Spanner and Autoscaler.
  D. Use granular instance sizing in Cloud Spanner and Autoscaler.

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  Explanation/Reference:

  Granular instance is available in Public Preview. With this feature, you can run workloads on Spanner at as low as 1/10th the cost of regular instances, https://cloud.google.com/blog/products/databases/get-more-out-of-spanner-with-granularinstance-sizing

• Question 104:

  You are working on a new centralized inventory management system to track items available in 200 stores, which each have 500 GB of data. You are planning a gradual rollout of the system to a few stores each week. You need to design an SQL database architecture that minimizes costs and user disruption during each regional rollout and can scale up or down on nights and holidays. What should you do?

  A. Use Oracle Real Application Cluster (RAC) databases on Bare Metal Solution for Oracle.
  B. Use sharded Cloud SQL instances with one or more stores per database instance.
  C. Use a Biglable cluster with autoscaling.
  D. Use Cloud Spanner with a custom autoscaling solution.
  D. Use Cloud Spanner with a custom autoscaling solution.

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  Explanation/Reference:

  https://cloud.google.com/spanner/docs/autoscaling-overview

  1.

  CloudSQL max out at 64TB, so unable to told 100TB of data. https://cloud.google.com/sql/docs/quotas#metrics_collection_limit

  2.

  Scale is done manually on SQL Cloud

• Question 105:

  You are using Compute Engine on Google Cloud and your data center to manage a set of MySQL databases in a hybrid configuration. You need to create replicas to scale reads and to offload part of the management operation. What should you do?

  A. Use external server replication.
  B. Use Data Migration Service.
  C. Use Cloud SQL for MySQL external replica.
  D. Use the mysqldump utility and binary logs.
  C. Use Cloud SQL for MySQL external replica.

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  Explanation/Reference:

  An external replica is a method that allows you to create a read-only copy of your Cloud SQL instance on an external server, such as a Compute Engine instance or an on-premises database server1. An external replica can help you scale reads and offload management operations from your data center to Google Cloud. You can also use an external replica for disaster recovery, migration, or reporting purposes1. To create an external replica, you need to configure a Cloud SQL instance that replicates to one or more replicas external to Cloud SQL, and a source representation instance that represents the source database server in Cloud SQL1. You also need to enable access on the Cloud SQL instance for the IP address of the external replica, create a replication user, and export and import the data from the source database server to the external replica1.

• Question 106:

  You need to redesign the architecture of an application that currently uses Cloud SQL for PostgreSQL. The users of the application complain about slow query response times. You want to enhance your application architecture to offer sub-millisecond query latency. What should you do?

  A. Configure Firestore, and modify your application to offload queries.
  B. Configure Bigtable, and modify your application to offload queries.
  C. Configure Cloud SQL for PostgreSQL read replicas to offload queries.
  D. Configure Memorystore, and modify your application to offload queries.
  D. Configure Memorystore, and modify your application to offload queries.

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  Explanation/Reference:

  "sub-millisecond latency" always involves Memorystore. Furthermore, as we are talking about a relational DB (Cloud SQL), BigTable is not a solution to be considered.

• Question 107:

  You are designing a highly available (HA) Cloud SQL for PostgreSQL instance that will be used by 100 databases. Each database contains 80 tables that were migrated from your on-premises environment to Google Cloud. The applications that use these databases are located in multiple regions in the US, and you need to ensure that read and write operations have low latency. What should you do?

  A. Deploy 2 Cloud SQL instances in the us-central1 region with HA enabled, and create read replicas in us-east1 and us-west1.
  B. Deploy 2 Cloud SQL instances in the us-central1 region, and create read replicas in us-east1 and us-west1.
  C. Deploy 4 Cloud SQL instances in the us-central1 region with HA enabled, and create read replicas in us-central1, us-east1, and us-west1.
  D. Deploy 4 Cloud SQL instances in the us-central1 region, and create read replicas in us-central1, us-east1 and us-west1.
  A. Deploy 2 Cloud SQL instances in the us-central1 region with HA enabled, and create read replicas in us-east1 and us-west1.

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  Explanation/Reference:

  https://cloud.google.com/sql/docs/mysql/quotas#table_limit

• Question 108:

  Your company is using Cloud SQL for MySQL with an internal (private) IP address and wants to replicate some tables into BigQuery in near-real time for analytics and machine learning. You need to ensure that replication is fast and reliable and uses Google-managed services. What should you do?

  A. Develop a custom data replication service to send data into BigQuery.
  B. Use Cloud SQL federated queries.
  C. Use Database Migration Service to replicate tables into BigQuery.
  D. Use Datastream to capture changes, and use Dataflow to write those changes to BigQuery.
  D. Use Datastream to capture changes, and use Dataflow to write those changes to BigQuery.

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  Explanation/Reference:

  "Datastream is a serverless and easy-to-use Change Data Capture (CDC) and replication service that allows you to synchronize data across heterogeneous databases, storage systems, and applications reliably and with minimal latency. Datastream supports change data streaming from Oracle and MySQL databases to Google Cloud Storage (GCS). The service offers streamlined integration with Dataflow templates to power up to date materialized views in BigQuery for analytics, replicate their databases into Cloud SQL or Cloud Spanner for database synchronization, or leverage the event stream directly from GCS to realize event-driven architectures."

• Question 109:

  You are managing a Cloud SQL for PostgreSQL instance in Google Cloud. You need to test the high availability of your Cloud SQL instance by performing a failover. You want to use the cloud command. What should you do?

  A. Use gcloud sql instances failover .
  B. Use gcloud sql instances failover .
  C. Use gcloud sql instances promote-replica .
  D. Use gcloud sql instances promote-replica .
  A. Use gcloud sql instances failover .

• Question 110:

  You are building an Android game that needs to store data on a Google Cloud serverless database. The database will log user activity, store user preferences, and receive in-game updates. The target audience resides in developing countries that have intermittent internet connectivity. You need to ensure that the game can synchronize game data to the backend database whenever an internet network is available. What should you do?

  A. Use Firestore.
  B. Use Cloud SQL with an external (public) IP address.
  C. Use an in-app embedded database.
  D. Use Cloud Spanner.
  A. Use Firestore.

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  Explanation/Reference:

  https://firebase.google.com/docs/firestore