AWS Certified Database - Specialty v1.0
Question 1
A global digital advertising company captures browsing metadata to contextually display relevant images, pages, and links to targeted users. A single page load can generate multiple events that need to be stored individually. The maximum size of an event is 200 KB and the average size is 10 KB. Each page load must query the user's browsing history to provide targeting recommendations. The advertising company expects over 1 billion page visits per day from users in the
United States, Europe, Hong Kong, and India. The structure of the metadata varies depending on the event. Additionally, the browsing metadata must be written and read with very low latency to ensure a good viewing experience for the users.
Which database solution meets these requirements?
- A. Amazon DocumentDB
- B. Amazon RDS Multi-AZ deployment
- C. Amazon DynamoDB global table
- D. Amazon Aurora Global Database
Answer : C
Reference:
https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/GlobalTables.html
Question 2
A Database Specialist modified an existing parameter group currently associated with a production Amazon RDS for SQL Server Multi-AZ DB instance. The change is associated with a static parameter type, which controls the number of user connections allowed on the most critical RDS SQL Server DB instance for the company. This change has been approved for a specific maintenance window to help minimize the impact on users.
How should the Database Specialist apply the parameter group change for the DB instance?
- A. Select the option to apply the change immediately
- B. Allow the preconfigured RDS maintenance window for the given DB instance to control when the change is applied
- C. Apply the change manually by rebooting the DB instance during the approved maintenance window
- D. Reboot the secondary Multi-AZ DB instance
Answer : D
Reference:
https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_Troubleshooting.html
Question 3
A Database Specialist is designing a new database infrastructure for a ride hailing application. The application data includes a ride tracking system that stores
GPS coordinates for all rides. Real-time statistics and metadata lookups must be performed with high throughput and microsecond latency. The database should be fault tolerant with minimal operational overhead and development effort.
Which solution meets these requirements in the MOST efficient way?
- A. Use Amazon RDS for MySQL as the database and use Amazon ElastiCache
- B. Use Amazon DynamoDB as the database and use DynamoDB Accelerator
- C. Use Amazon Aurora MySQL as the database and use Auroraג€™s buffer cache
- D. Use Amazon DynamoDB as the database and use Amazon API Gateway
Answer : D
Reference:
https://aws.amazon.com/solutions/case-studies/lyft/
Question 4
A company is using an Amazon Aurora PostgreSQL DB cluster with an xlarge primary instance master and two large Aurora Replicas for high availability and read-only workload scaling. A failover event occurs and application performance is poor for several minutes. During this time, application servers in all Availability
Zones are healthy and responding normally.
What should the company do to eliminate this application performance issue?
- A. Configure both of the Aurora Replicas to the same instance class as the primary DB instance. Enable cache coherence on the DB cluster, set the primary DB instance failover priority to tier-0, and assign a failover priority of tier-1 to the replicas.
- B. Deploy an AWS Lambda function that calls the DescribeDBInstances action to establish which instance has failed, and then use the PromoteReadReplica operation to promote one Aurora Replica to be the primary DB instance. Configure an Amazon RDS event subscription to send a notification to an Amazon SNS topic to which the Lambda function is subscribed.
- C. Configure one Aurora Replica to have the same instance class as the primary DB instance. Implement Aurora PostgreSQL DB cluster cache management. Set the failover priority to tier-0 for the primary DB instance and one replica with the same instance class. Set the failover priority to tier-1 for the other replicas.
- D. Configure both Aurora Replicas to have the same instance class as the primary DB instance. Implement Aurora PostgreSQL DB cluster cache management. Set the failover priority to tier-0 for the primary DB instance and to tier-1 for the replicas.
Answer : D
Question 5
A company has a database monitoring solution that uses Amazon CloudWatch for its Amazon RDS for SQL Server environment. The cause of a recent spike in
CPU utilization was not determined using the standard metrics that were collected. The CPU spike caused the application to perform poorly, impacting users. A
Database Specialist needs to determine what caused the CPU spike.
Which combination of steps should be taken to provide more visibility into the processes and queries running during an increase in CPU load? (Choose two.)
- A. Enable Amazon CloudWatch Events and view the incoming T-SQL statements causing the CPU to spike.
- B. Enable Enhanced Monitoring metrics to view CPU utilization at the RDS SQL Server DB instance level.
- C. Implement a caching layer to help with repeated queries on the RDS SQL Server DB instance.
- D. Use Amazon QuickSight to view the SQL statement being run.
- E. Enable Amazon RDS Performance Insights to view the database load and filter the load by waits, SQL statements, hosts, or users.
Answer : BE
Question 6
A company is using Amazon with Aurora Replicas for read-only workload scaling. A Database Specialist needs to split up two read-only applications so each application always connects to a dedicated replica. The Database Specialist wants to implement load balancing and high availability for the read-only applications.
Which solution meets these requirements?
- A. Use a specific instance endpoint for each replica and add the instance endpoint to each read-only application connection string.
- B. Use reader endpoints for both the read-only workload applications.
- C. Use a reader endpoint for one read-only application and use an instance endpoint for the other read-only application.
- D. Use custom endpoints for the two read-only applications.
Answer : B
Reference:
https://rimzy.net/category/amazon-rds/page/4/
Question 7
An online gaming company is planning to launch a new game with Amazon DynamoDB as its data store. The database should be designated to support the following use cases:
✑ Update scores in real time whenever a player is playing the game.
✑ Retrieve a player's score details for a specific game session.
A Database Specialist decides to implement a DynamoDB table. Each player has a unique user_id and each game has a unique game_id.
Which choice of keys is recommended for the DynamoDB table?
- A. Create a global secondary index with game_id as the partition key
- B. Create a global secondary index with user_id as the partition key
- C. Create a composite primary key with game_id as the partition key and user_id as the sort key
- D. Create a composite primary key with user_id as the partition key and game_id as the sort key
Answer : B
Reference:
https://aws.amazon.com/blogs/database/amazon-dynamodb-gaming-use-cases-and-design-patterns/
Question 8
A Database Specialist migrated an existing production MySQL database from on-premises to an Amazon RDS for MySQL DB instance. However, after the migration, the database needed to be encrypted at rest using AWS KMS. Due to the size of the database, reloading, the data into an encrypted database would be too time-consuming, so it is not an option.
How should the Database Specialist satisfy this new requirement?
- A. Create a snapshot of the unencrypted RDS DB instance. Create an encrypted copy of the unencrypted snapshot. Restore the encrypted snapshot copy.
- B. Modify the RDS DB instance. Enable the AWS KMS encryption option that leverages the AWS CLI.
- C. Restore an unencrypted snapshot into a MySQL RDS DB instance that is encrypted.
- D. Create an encrypted read replica of the RDS DB instance. Promote it the master.
Answer : A
Question 9
A Database Specialist is planning to create a read replica of an existing Amazon RDS for MySQL Multi-AZ DB instance. When using the AWS Management
Console to conduct this task, the Database Specialist discovers that the source RDS DB instance does not appear in the read replica source selection box, so the read replica cannot be created.
What is the most likely reason for this?
- A. The source DB instance has to be converted to Single-AZ first to create a read replica from it.
- B. Enhanced Monitoring is not enabled on the source DB instance.
- C. The minor MySQL version in the source DB instance does not support read replicas.
- D. Automated backups are not enabled on the source DB instance.
Answer : D
Reference:
https://aws.amazon.com/rds/features/read-replicas/
Question 10
A Database Specialist has migrated an on-premises Oracle database to Amazon Aurora PostgreSQL. The schema and the data have been migrated successfully.
The on-premises database server was also being used to run database maintenance cron jobs written in Python to perform tasks including data purging and generating data exports. The logs for these jobs show that, most of the time, the jobs completed within 5 minutes, but a few jobs took up to 10 minutes to complete. These maintenance jobs need to be set up for Aurora PostgreSQL.
How can the Database Specialist schedule these jobs so the setup requires minimal maintenance and provides high availability?
- A. Create cron jobs on an Amazon EC2 instance to run the maintenance jobs following the required schedule.
- B. Connect to the Aurora host and create cron jobs to run the maintenance jobs following the required schedule.
- C. Create AWS Lambda functions to run the maintenance jobs and schedule them with Amazon CloudWatch Events.
- D. Create the maintenance job using the Amazon CloudWatch job scheduling plugin.
Answer : D
Reference:
https://docs.aws.amazon.com/systems-manager/latest/userguide/mw-cli-task-options.html
Question 11
A company has an Amazon RDS Multi-AZ DB instances that is 200 GB in size with an RPO of 6 hours. To meet the company's disaster recovery policies, the database backup needs to be copied into another Region. The company requires the solution to be cost-effective and operationally efficient.
What should a Database Specialist do to copy the database backup into a different Region?
- A. Use Amazon RDS automated snapshots and use AWS Lambda to copy the snapshot into another Region
- B. Use Amazon RDS automated snapshots every 6 hours and use Amazon S3 cross-Region replication to copy the snapshot into another Region
- C. Create an AWS Lambda function to take an Amazon RDS snapshot every 6 hours and use a second Lambda function to copy the snapshot into another Region
- D. Create a cross-Region read replica for Amazon RDS in another Region and take an automated snapshot of the read replica
Answer : D
Reference:
https://aws.amazon.com/blogs/database/implementing-a-disaster-recovery-strategy-with-amazon-rds/
Question 12
An Amazon RDS EBS-optimized instance with Provisioned IOPS (PIOPS) storage is using less than half of its allocated IOPS over the course of several hours under constant load. The RDS instance exhibits multi-second read and write latency, and uses all of its maximum bandwidth for read throughput, yet the instance uses less than half of its CPU and RAM resources.
What should a Database Specialist do in this situation to increase performance and return latency to sub-second levels?
- A. Increase the size of the DB instance storage
- B. Change the underlying EBS storage type to General Purpose SSD (gp2)
- C. Disable EBS optimization on the DB instance
- D. Change the DB instance to an instance class with a higher maximum bandwidth
Answer : B
Question 13
After restoring an Amazon RDS snapshot from 3 days ago, a company's Development team cannot connect to the restored RDS DB instance. What is the likely cause of this problem?
- A. The restored DB instance does not have Enhanced Monitoring enabled
- B. The production DB instance is using a custom parameter group
- C. The restored DB instance is using the default security group
- D. The production DB instance is using a custom option group
Answer : B
Question 14
A gaming company has implemented a leaderboard in AWS using a Sorted Set data structure within Amazon ElastiCache for Redis. The ElastiCache cluster has been deployed with cluster mode disabled and has a replication group deployed with two additional replicas. The company is planning for a worldwide gaming event and is anticipating a higher write load than what the current cluster can handle.
Which method should a Database Specialist use to scale the ElastiCache cluster ahead of the upcoming event?
- A. Enable cluster mode on the existing ElastiCache cluster and configure separate shards for the Sorted Set across all nodes in the cluster.
- B. Increase the size of the ElastiCache cluster nodes to a larger instance size.
- C. Create an additional ElastiCache cluster and load-balance traffic between the two clusters.
- D. Use the EXPIRE command and set a higher time to live (TTL) after each call to increment a given key.
Answer : B
Reference:
https://aws.amazon.com/blogs/database/work-with-cluster-mode-on-amazon-elasticache-for-redis/
Question 15
An ecommerce company has tasked a Database Specialist with creating a reporting dashboard that visualizes critical business metrics that will be pulled from the core production database running on Amazon Aurora. Data that is read by the dashboard should be available within 100 milliseconds of an update.
The Database Specialist needs to review the current configuration of the Aurora DB cluster and develop a cost-effective solution. The solution needs to accommodate the unpredictable read workload from the reporting dashboard without any impact on the write availability and performance of the DB cluster.
Which solution meets these requirements?
- A. Turn on the serverless option in the DB cluster so it can automatically scale based on demand.
- B. Provision a clone of the existing DB cluster for the new Application team.
- C. Create a separate DB cluster for the new workload, refresh from the source DB cluster, and set up ongoing replication using AWS DMS change data capture (CDC).
- D. Add an automatic scaling policy to the DB cluster to add Aurora Replicas to the cluster based on CPU consumption.
Answer : A