Amazon DBS-C01 Online Practice Questions and Exam Preparation

Amazon DBS-C01 Online Questions & Answers

• Question 301:

  A company hosts a 2 TB Oracle database in its on-premises data center. A database specialist is migrating the database from on premises to an Amazon Aurora PostgreSQL database on AWS.

  The database specialist identifies a problem that relates to compatibility Oracle stores metadata in its data dictionary in uppercase, but PostgreSQL stores the metadata in lowercase. The database specialist must resolve this problem to

  complete the migration.

  What is the MOST operationally efficient solution that meets these requirements?

  A. Override the default uppercase format of Oracle schema by encasing object names in quotation marks during creation.
  B. Use AWS Database Migration Service (AWS DMS) mapping rules with rule-action as convert-lowercase.
  C. Use the AWS Schema Conversion Tool conversion agent to convert the metadata from uppercase to lowercase.
  D. Use an AWS Glue job that is attached to an AWS Database Migration Service (AWS DMS) replication task to convert the metadata from uppercase to lowercase.
  B. Use AWS Database Migration Service (AWS DMS) mapping rules with rule-action as convert-lowercase.

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  Explanation/Reference:

  https://aws.amazon.com/premiumsupport/knowledge-center/dms-mapping- oracle-postgresql/

• Question 302:

  A media company is using Amazon RDS for PostgreSQL to store user data. The RDS DB instance currently has a publicly accessible setting enabled and is hosted in a public subnet. Following a recent AWS Well- Architected Framework review, a Database Specialist was given new security requirements.

  Only certain on-premises corporate network IPs should connect to the DB instance. Connectivity is allowed from the corporate network only.

  Which combination of steps does the Database Specialist need to take to meet these new requirements? (Choose three.)

  A. Modify the pg_hba.conf file. Add the required corporate network IPs and remove the unwanted IPs.
  B. Modify the associated security group. Add the required corporate network IPs and remove the unwanted IPs.
  C. Move the DB instance to a private subnet using AWS DMS.
  D. Enable VPC peering between the application host running on the corporate network and the VPC associated with the DB instance.
  E. Disable the publicly accessible setting.
  F. Connect to the DB instance using private IPs and a VPN.
  B. Modify the associated security group. Add the required corporate network IPs and remove the unwanted IPs.
  E. Disable the publicly accessible setting.
  F. Connect to the DB instance using private IPs and a VPN.

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  Explanation/Reference:

  https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_VPC.WorkingWithRD SInstanceinaVPC.html#USER_VPC.Hiding

• Question 303:

  A company is going to use an Amazon Aurora PostgreSQL DB cluster for an application backend. The DB cluster contains some tables with sensitive data. A Database Specialist needs to control the access privileges at the table level. How can the Database Specialist meet these requirements?

  A. Use AWS IAM database authentication and restrict access to the tables using an IAM policy.
  B. Configure the rules in a NACL to restrict outbound traffic from the Aurora DB cluster.
  C. Execute GRANT and REVOKE commands that restrict access to the tables containing sensitive data.
  D. Define access privileges to the tables containing sensitive data in the pg_hba.conf file.
  C. Execute GRANT and REVOKE commands that restrict access to the tables containing sensitive data.

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  Explanation/Reference:

  Reference: https://aws.amazon.com/blogs/database/managing-postgresql-users-and-roles/

• Question 304:

  A company is hosting critical business data in an Amazon Redshift cluster. Due to the sensitive nature of the data, the cluster is encrypted at rest using AWS KMS. As a part of disaster recovery requirements, the company needs to copy the Amazon Redshift snapshots to another Region.

  Which steps should be taken in the AWS Management Console to meet the disaster recovery requirements?

  A. Create a new KMS customer master key in the source Region. Switch to the destination Region, enable Amazon Redshift cross-Region snapshots, and use the KMS key of the source Region.
  B. Create a new IAM role with access to the KMS key. Enable Amazon Redshift cross- Region replication using the new IAM role, and use the KMS key of the source Region.
  C. Enable Amazon Redshift cross-Region snapshots in the source Region, and create a snapshot copy grant and use a KMS key in the destination Region.
  D. Create a new KMS customer master key in the destination Region and create a new IAM role with access to the new KMS key. Enable Amazon Redshift cross-Region replication in the source Region and use the KMS key of the destination Region.
  C. Enable Amazon Redshift cross-Region snapshots in the source Region, and create a snapshot copy grant and use a KMS key in the destination Region.

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  Explanation/Reference:

  If you want to enable cross-Region snapshot copy for an AWS KMS璭ncrypted cluster, you must configure a snapshot copy grant for a root key in the destination AWS Region Source- Region : configure a cross-Region snapshot for an AWS KMS璭ncrypted cluster In Destination AWS Region : choose the AWS Region to which to copy snapshots. https://docs.aws.amazon.com/redshift/latest/mgmt/managing-snapshots- console.html#xregioncopy-kms-encrypted-snapshot

• Question 305:

  A database specialist is launching a test graph database using Amazon Neptune for the first time. The database specialist needs to insert millions of rows of test observations from a .csv file that is stored in Amazon S3. The database specialist has been using a series of API calls to upload the data to the Neptune DB instance.

  Which combination of steps would allow the database specialist to upload the data faster? (Choose three.)

  A. Ensure Amazon Cognito returns the proper AWS STS tokens to authenticate the Neptune DB instance to the S3 bucket hosting the CSV file.
  B. Ensure the vertices and edges are specified in different .csv files with proper header column formatting.
  C. Use AWS DMS to move data from Amazon S3 to the Neptune Loader.
  D. Curl the S3 URI while inside the Neptune DB instance and then run the addVertex or addEdge commands.
  E. Ensure an IAM role for the Neptune DB instance is configured with the appropriate permissions to allow access to the file in the S3 bucket.
  F. Create an S3 VPC endpoint and issue an HTTP POST to the database's loader endpoint.
  B. Ensure the vertices and edges are specified in different .csv files with proper header column formatting.
  E. Ensure an IAM role for the Neptune DB instance is configured with the appropriate permissions to allow access to the file in the S3 bucket.
  F. Create an S3 VPC endpoint and issue an HTTP POST to the database's loader endpoint.

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  Explanation/Reference:

  Correct Answer: B, E, F

  from Amazon documents:

  To upload data faster to a Neptune DB instance from a .csv file stored in Amazon S3, the database specialist should use the Neptune Bulk Loader, which is a feature that allows you to load data from external files directly into a Neptune DB

  instance1. The Neptune Bulk Loader is faster and has less overhead than the API calls, such as SPARQL INSERT statements or Gremlin addV and addE steps2. The Neptune Bulk Loader supports both RDF and Gremlin data formats1.

  To use the Neptune Bulk Loader, the database specialist needs to do the following13:

  Ensure the vertices and edges are specified in different .csv files with proper header column formatting. This is required for the Gremlin data format, which uses two .csv files: one for vertices and one for edges. The first row of each file must

  contain the column names, which must match the property names of the graph elements. The files must also have a column named ~id for vertices and ~from and ~to for edges, which specify the unique identifiers of the graph elements1.

  Ensure an IAM role for the Neptune DB instance is configured with the appropriate permissions to allow access to the file in the S3 bucket. This is required for the Neptune DB instance to read the data from the S3 bucket. The IAM role must

  have a trust policy that allows Neptune to assume the role, and a permissions policy that allows access to the S3 bucket and objects3.

  Create an S3 VPC endpoint and issue an HTTP POST to the database's loader endpoint. This is required for the Neptune DB instance to communicate with the S3 bucket without going through the public internet. The S3 VPC endpoint must

  be in the same VPC as the Neptune DB instance. The HTTP POST request must specify the source parameter as the S3 URI of the .csv file, and optionally other parameters such as format, failOnError, parallelism, etc1. Therefore, option B,

  E, and F are the correct steps to upload the data faster. Option A is not necessary because Amazon Cognito is not used for authenticating the Neptune DB instance to the S3 bucket. Option C is not suitable because AWS DMS is not

  designed for loading graph data into Neptune. Option D is not efficient because curling the S3 URI and running the addVertex or addEdge commands will be slower and more costly than using the Neptune Bulk Loader.

• Question 306:

  A company has an AWS CloudFormation template written in JSON that is used to launch new Amazon RDS for MySQL DB instances. The security team has asked a database specialist to ensure that the master password is automatically rotated every 30 days for all new DB instances that are launched using the template.

  What is the MOST operationally efficient solution to meet these requirements?

  A. Save the password in an Amazon S3 object. Encrypt the S3 object with an AWS KMS key. Set the KMS key to be rotated every 30 days by setting the EnableKeyRotation property to true. Use a CloudFormation custom resource to read the S3 object to extract the password.
  B. Create an AWS Lambda function to rotate the secret. Modify the CloudFormation template to add an AWS::SecretsManager::RotationSchedule resource. Configure the RotationLambdaARN value and, for the RotationRules property, set the AutomaticallyAfterDays parameter to 30.
  C. Modify the CloudFormation template to use the AWS KMS key as the database password. Configure an Amazon EventBridge rule to invoke the KMS API to rotate the key every 30 days by setting the ScheduleExpression parameter to ***/30***.
  D. Integrate the Amazon RDS for MySQL DB instances with AWS IAM and centrally manage the master database user password.
  B. Create an AWS Lambda function to rotate the secret. Modify the CloudFormation template to add an AWS::SecretsManager::RotationSchedule resource. Configure the RotationLambdaARN value and, for the RotationRules property, set the AutomaticallyAfterDays parameter to 30.

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  Explanation/Reference:

  https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws- resource-secretsmanager-rotationschedule.html

• Question 307:

  A social media company is using Amazon DynamoDB to store user profile data and user activity data. Developers are reading and writing the data, causing the size of the tables to grow significantly. Developers have started to face performance bottlenecks with the tables.

  Which solution should a database specialist recommend to read items the FASTEST without consuming all the provisioned throughput for the tables?

  A. Use the Scan API operation in parallel with many workers to read all the items. Use the Query API operation to read multiple items that have a specific partition key and sort key. Use the GetItem API operation to read a single item.
  B. Use the Scan API operation with a filter expression that allows multiple items to be read. Use the Query API operation to read multiple items that have a specific partition key and sort key. Use the GetItem API operation to read a single item.
  C. Use the Scan API operation with a filter expression that allows multiple items to be read. Use the Query API operation to read a single item that has a specific primary key. Use the BatchGetItem API operation to read multiple items.
  D. Use the Scan API operation in parallel with many workers to read all the items. Use the Query API operation to read a single item that has a specific primary key Use the BatchGetItem API operation to read multiple items.
  B. Use the Scan API operation with a filter expression that allows multiple items to be read. Use the Query API operation to read multiple items that have a specific partition key and sort key. Use the GetItem API operation to read a single item.

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  Explanation/Reference:

  https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/SQLtoNoSQL.Rea dData.html

• Question 308:

  A company requires near-real-time notifications when changes are made to Amazon RDS DB security groups.

  Which solution will meet this requirement with the LEAST operational overhead?

  A. Configure an RDS event notification subscription for DB security group events.
  B. Create an AWS Lambda function that monitors DB security group changes. Create an Amazon Simple Notification Service (Amazon SNS) topic for notification.
  C. Turn on AWS CloudTrail. Configure notifications for the detection of changes to DB security groups.
  D. Configure an Amazon CloudWatch alarm for RDS metrics about changes to DB security groups.
  A. Configure an RDS event notification subscription for DB security group events.

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  Explanation/Reference:

  https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_Events.Messages.htm l#USER_Events.Messages.security-group

• Question 309:

  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.
  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.

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  Explanation/Reference:

  https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/AuroraPostgreSQL.clu ster-cache-mgmt.html

  https://aws.amazon.com/blogs/database/introduction-to-aurora-postgresql-cluster-cache- management/

  "You can customize the order in which your Aurora Replicas are promoted to the primary instance after a failure by assigning each replica a priority. Priorities range from 0 for the first priority to 15 for the last priority. If the primary instance

  fails, Amazon RDS promotes the Aurora Replica with the better priority to the new primary instance. You can modify the priority of an Aurora Replica at any time. Modifying the priority doesn't trigger a failover. More than one Aurora Replica

  can share the same priority, resulting in promotion tiers. If two or more Aurora Replicas share the same priority, then Amazon RDS promotes the replica that is largest in size. If two or more Aurora Replicas share the same priority and size,

  then Amazon RDS promotes an arbitrary replica in the same promotion tier. "

  Amazon Aurora with PostgreSQL compatibility now supports cluster cache management, providing a faster path to full performance if there's a failover. With cluster cache management, you designate a specific reader DB instance in your

  Aurora PostgreSQL cluster as the failover target. Cluster cache management keeps the data in the designated reader's cache synchronized with the data in the read-write instance's cache. If a failover occurs, the designated reader is

  promoted to be the new read-write instance, and workloads benefit immediately from the data in its cache.

• Question 310:

  A user has a non-relational key-value database. The user is looking for a fully managed AWS service that will offload the administrative burdens of operating and scaling distributed databases. The solution must be cost- effective and able to handle unpredictable application traffic.

  What should a Database Specialist recommend for this user?

  A. Create an Amazon DynamoDB table with provisioned capacity mode
  B. Create an Amazon DocumentDB cluster
  C. Create an Amazon DynamoDB table with on-demand capacity mode
  D. Create an Amazon Aurora Serverless DB cluster
  C. Create an Amazon DynamoDB table with on-demand capacity mode

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  Explanation/Reference:

  Reference: https://aws.amazon.com/dynamodb/

  Key-value database -> DynamoDB Capable of dealing with unexpected application traffic - > on-demand capacity mode

  A key-value database is a type of nonrelational database that uses a simple key-value method to store data. A key-value database stores data as a collection of key-value pairs in which a key serves as a unique identifier. On-demand mode is a good option to create new tables with unknown workloads. https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/HowItWorks.Read WriteCapacityMode.html#HowItWorks.OnDemand