DBS-C01 Question Bank · Latest 50 Questions Free Preview (Page 1/5)
Questions 1–10 of the latest 50 DBS-C01 questions (5 pages total), with answers and explanations, no login required. Practice all 376 questions online.
Question 1 · No. 327 · Single choice
A legal research company wants to build a recommendation engine on AWS that connects datasets to help lawyers create legal arguments. The recommendation engine will collect millions of unstructured text documents from third-party sources to identify connections between documents without users needing to manually compare the documents. Which solution will meet these requirements with the LEAST operational overhead?
- A. Build a graph-based recommendation engine by using Amazon Neptune. Search the documents for vertices with relationships among the different sources to connect.
- B. Create an AWS Lambda application in which the documents are uploaded into Amazon S3. Populate Amazon DynamoDB tables with the metadata of the documents for users to search.
- C. Develop a serverless document scanner by using Amazon Textract to analyze the text from the various sources. Store the detected text in an Amazon Aurora database for analysis.
- D. Define the data sources in an Amazon S3 data lake. Analyze the documents by using AWS Glue. Query the documents for relationships by using Amazon Athena.
Answer: A
Explanation: Answer is A. Amazon Neptune is a purpose-built, high-performance graph database engine that makes it easy to establish and navigate highly connected datasets. It is suitable for the large number of unstructured text documents and recognizing the connections, making it the best solution with least operational overhead.
Question 2 · No. 328 · Single choice
A company recently created a snapshot of an Amazon RDS for PostgreSQL DB instance that hosts a production database. The company created a new DB instance from the snapshot to test a new application feature while providing isolation from the production database. During testing of the new application feature, the company noticed that read latency on the new database was higher than normal. A database specialist needs to resolve the latency issue. Which solution will meet these requirements with the MOST operational efficiency?
- A. Log in to the database by using the PostgreSQL administration tool. Issue a SELECT * command against each table in the database.
- B. Create a new parameter group and set the max_connections parameter to 100. Assign the parameter group to the new database. Apply the changes immediately.
- C. Edit the default parameter group for the matching PostgreSQL engine. Set the max_connections parameter to 100. Reboot the new database to pick up the changes to the parameter group.
- D. Login to the database by using the PostgreSQL administration tool. Issue the VACUUM (ANALYZE, DISABLE_PAGE_SKIPPING) command.
Answer: B
Question 3 · No. 329 · Multiple choice
A database administrator is reviewing the deployment of an application that uses Amazon DynamoDB. A fleet of Amazon EC2 application instances accesses the database. The database administrator notices that EC2 instances are using public IP addresses to access the database and that the database is available to the internet. Company policy requires that all corporate data must be accessed privately and that external access from the internet is not allowed. Which combination of steps will ensure that the DynamoDB database meets these requirements? (Choose two.)
- A. Configure the DynamoDB security group and network ACLs to block external access.
- B. Create an AWS PrivateLink VPC endpoint for DynamoDUpdate the VPC route table.
- C. Create a gateway VPC endpoint for DynamoDB. Update the VPC route table.
- D. Provision a NAT gateway to access DynamoDB. Update the VPC route table.
- E. Use the aws:sourceVpce condition for all the IAM roles that provision access to the table.
Answer: B, E
Explanation: Answer is B, E. Solution B is accurate because it helps create a private connection between the VPC and the DynamoDB without the need to traverse the public internet. Option E is also valid because it sets the condition that access to the DynamoDB table will only be granted if the requests come from the specific VPC endpoint, thereby ensuring no external access.
Question 4 · No. 330 · Single choice
A company has a 250 GB Amazon RDS Multi-AZ DB instance. The company’s disaster recovery policy requires an RPO of 6 hours in a second AWS Region. Which solution will meet these requirements MOST cost-effectively?
- A. Use RDS automated snapshots. Create an AWS Lambda function to copy the snapshot to a second Region.
- B. Use RDS automated snapshots every 6 hours. Use Amazon S3 Cross-Region Replication to copy the snapshot to a second Region.
- C. Use AWS Backup to take an RDS snapshot every 6 hours and to copy the snapshot to a second Region.
- D. Create an RDS cross-Region read replica in a second Region. Use AWS Backup to take an automated snapshot of the read replica every 6 hours.
Answer: A
Explanation: Answer is A. Option A is the most cost-effective as it uses RDS automated snapshots and an AWS Lambda function. Lambda is cheaper than using an AWS Backup or S3 Cross-Region replication.
Question 5 · No. 331 · Multiple choice
A company uses an Amazon RDS for PostgreSQL database in the us-east-2 Region. The company wants to have a copy of the database available in the us-west-2 Region as part of a new disaster recovery strategy. A database architect needs to create the new database. There can be little to no downtime to the source database. The database architect has decided to use AWS Database Migration Service (AWS DMS) to replicate the database across Regions. The database architect will use full load mode and then will switch to change data capture (CDC) mode. Which parameters must the database architect configure to support CDC mode for the RDS for PostgreSQL database? (Choose three.)
- A. Set wal_level = logical.
- B. Set wal_level = replica.
- C. Set max_replication_slots to 1 or more, depending on the number of DMS tasks.
- D. Set max_replication_slots to 0 to support dynamic allocation of slots.
- E. Set wal_sender_timeout to 20,000 milliseconds.
- F. Set wal_sender_timeout to 5,000 milliseconds.
Answer: A, C, E
Explanation: Answer is A, C, E. To enable change data capture (CDC) mode for RDS for PostgreSQL with AWS DMS, the database architect needs to set wal_level to logical (A), set max_replication_slots to 1 or more depending on the number of DMS tasks (C), and set wal_sender_timeout to a sufficiently high value (E). Option B is not correct because wal_level should be set to logical not replica for CDC. Option D is not correct because max_replication_slots should be 1 or more for concurrent DMS tasks not set to 0. Option F is not correct because increasing wal_sender_timeout to a sufficient high value like 20000 milliseconds or more ensures that connections are not killed prematurely.
Question 6 · No. 332 · Single choice
A database specialist is designing a disaster recovery (DR) strategy for a highly available application that is in development. The application uses an Amazon DynamoDB table as its data store. The application requires an RTO of 1 minute and an RPO of 2 minutes. Which DR strategy for the DynamoDB table will meet these requirements with the MOST operational efficiency?
- A. Create a DynamoDB stream and an AWS Lambda function. Configure the Lambda function to process the stream and copy the data to a table in another AWS Region.
- B. Use a DynamoDB global table replica in another AWS Region. Activate point-in-time recovery for both tables.
- C. Use a DynamoDB Accelerator (DAX) table in another AWS Region. Activate point-in-time recovery for the table.
- D. Create an AWS Backup plan. Assign the DynamoDB table as a resource.
Answer: B
Explanation: Answer is B. Using a DynamoDB global table replica in another AWS Region with point-in-time recovery for both tables will fulfill the disaster recovery strategy requirements while also achieving the most operational efficiency. This option allows for data replication across regions, maintaining high availability, and at the same time, adheres to the given RTO and RPO values.
Question 7 · No. 333 · Single choice
A company has an existing system that uses a single-instance Amazon DocumentDB (with MongoDB compatibility) cluster. Read requests account for 75% of the system queries. Write requests are expected to increase by 50% after an upcoming global release. A database specialist needs to design a solution that improves the overall database performance without creating additional application overhead. Which solution will meet these requirements?
- A. Recreate the cluster with a shared cluster volume. Add two instances to serve both read requests and write requests.
- B. Add one read replica instance. Activate a shared cluster volume. Route all read queries to the read replica instance.
- C. Add one read replica instance. Set the read preference to secondary preferred.
- D. Add one read replica instance. Update the application to route all read queries to the read replica instance.
Answer: D
Explanation: Answer is D. The best method to enhance the performance given more read operations are expected would be to create a read replica and route all read queries to that replica. This method improves read performance and can absorb the impact of the increased traffic without adding overhead to the application, unlike option B which involves activating a shared cluster volume.
Question 8 · No. 334 · Single choice
A company uses multiple AWS accounts in AWS Organizations to separate development teams that work on different applications. Each AWS account contains multiple applications that run in the default VPC with interface endpoints. The applications need access to the same underlying data in an Amazon Aurora PostgreSQL DB cluster in one of the AWS accounts. Which solution will meet these requirements in the MOST operationally efficient way?
- A. Use AWS Resource Access Manager (AWS RAM) to share the subnet that contains the database. Create an Amazon RDS Proxy endpoint for the other applications to access.
- B. Use VPC peering to connect the VPCs of the other AWS accounts to the subnet that contains the database.
- C. Create an Amazon S3 bucket that stores database backups. Configure replication to S3 buckets in the other accounts. Restore the backups in the other AWS accounts.
- D. Create an interface VPC endpoint for the Amazon RDS API. Attach an endpoint policy that grants the other AWS accounts access to the database.
Answer: A
Explanation: Answer is A. AWS Resource Access Manager (RAM) is a service that enables you to easily and securely share your AWS resources with any AWS account or within your AWS Organization. It enables the sharing of subnets and Transit Gateways across accounts, simplifying network setup. Most importantly, by leveraging AWS RAM for this scenario, the need to expose your database to the internet is eliminated which enhances security. Using Amazon RDS Proxy can allow for connections to flow through to the database without a large number of connections directly impacting the database.
Question 9 · No. 335 · Single choice
A company that is located in the United States wants to expand its operations in Asia. The company’s data in the us-west-2 Region is stored in an Amazon DynamoD8 table. The company’s development team in the ap-northeast-1 Region needs to perform user acceptance testing (UAT) and several other performance feasibility tests with a copy of production data from us-west-2. The feasibility tests do not need to be run on data that is updated in real time. Which solution will make data available from us-west-2 to ap-northeast-1 MOST cost-effectively?
- A. Create a new DynamoDB table in ap-northeast-1. Create an AWS Glue job to perform a data export from the DynamoDB table in us-west-2. Import the same data into the DynamoDB table in ap-northeast-1.
- B. Enable DynamoDB Streams on the DynamoDB table in us-west-2. Create a new DynamoDB table in ap-northeast-1. Create an AWS Lambda function to poll the DynamoDB table stream in us-west-2 and to deliver batch records from the stream to the new DynamoDB table in ap-northeast-1.
- C. Use point-in-time recovery to restore the DynamoDB table from us-west-2 lo ap-northeast-1.
- D. Enable DynamoDB Streams on the DynamoDB table in us-west-2. Add ap-northeast-1 to the DynamoDB global tables setting in us-west-2.
Answer: A
Explanation: Answer is A. Creating a new DynamoDB table in the ap-northeast-1 region and importing data using an AWS Glue job is the most cost-effective solution. Though options B and D are valid solutions, they involve additional costs of using DynamoDB Streams and AWS Lambda function or global tables, while option C is not possible because point-in-time recovery cannot restore data cross region.
Question 10 · No. 336 · Multiple choice
A company provisioned a three-tier application by using AWS CloudFormation and an Amazon RDS DB instance. During a test, a database administrator accidentally deleted the CloudFormation stack. The results were a deletion of all the resources, including the DB instance, and a loss of critical data. The company wants to prevent accidental deletion of a DB instance from happening in the future. Which solutions will meet this requirement? (Choose two.)
- A. Set the deletion policy of the stack to Retain.
- B. Set the deletion policy of the RDS resource to Retain.
- C. Set the deletion policy of the stack to Snapshot.
- D. Enable termination protection for the RDS resource.
- E. Enable termination protection for the stack.
Answer: B, D
Explanation: Answer is B, D. Setting the deletion policy of the RDS resource to Retain (option B) and enabling termination protection for the RDS resource (option D) will prevent accidental deletion of a DB instance. The deletion policy Retain means that AWS CloudFormation keeps the resource when the stack is deleted. Termination protection for an RDS instance prevents accidental termination or deletion.