DBS-C01 Free Practice Test

A company is building a new web platform where user requests trigger an AWS Lambda function that performs an insert into an Amazon Aurora MySQL DB cluster. Initial tests with less than 10 users on the new platform yielded successful execution and fast response times. However, upon more extensive tests with the actual target of 3,000 concurrent users, Lambda functions are unable to connect to the DB cluster and receive too many connections errors.
Which of the following will resolve this issue?

1. A. Edit the my.cnf file for the DB cluster to increase max_connections
2. B. Increase the instance size of the DB cluster
3. C. Change the DB cluster to Multi-AZ
4. D. Increase the number of Aurora Replicas

Correct Answer: B

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?

1. A. The source DB instance has to be converted to Single-AZ first to create a read replica from it.
2. B. Enhanced Monitoring is not enabled on the source DB instance.
3. C. The minor MySQL version in the source DB instance does not support read replicas.
4. D. Automated backups are not enabled on the source DB instance.

Correct Answer: D

A Database Specialist is migrating a 2 TB Amazon RDS for Oracle DB instance to an RDS for PostgreSQL DB instance using AWS DMS. The source RDS Oracle DB instance is in a VPC in the us-east-1 Region. The target RDS for PostgreSQL DB instance is in a VPC in the use-west-2 Region.
Where should the AWS DMS replication instance be placed for the MOST optimal performance?

1. A. In the same Region and VPC of the source DB instance
2. B. In the same Region and VPC as the target DB instance
3. C. In the same VPC and Availability Zone as the target DB instance
4. D. In the same VPC and Availability Zone as the source DB instance

Correct Answer: D

A company wants to migrate its existing on-premises Oracle database to Amazon Aurora PostgreSQL. The migration must be completed with minimal downtime using AWS DMS. A Database Specialist must validate that the data was migrated accurately from the source to the target before the cutover. The migration must have minimal impact on the performance of the source database.
Which approach will MOST effectively meet these requirements?

1. A. Use the AWS Schema Conversion Tool (AWS SCT) to convert source Oracle database schemas to the target Aurora DB cluste
2. B. Verify the datatype of the columns.
3. C. Use the table metrics of the AWS DMS task created for migrating the data to verify the statistics for the tables being migrated and to verify that the data definition language (DDL) statements are completed.
4. D. Enable the AWS Schema Conversion Tool (AWS SCT) premigration validation and review the premigrationchecklist to make sure there are no issues with the conversion.
5. E. Enable AWS DMS data validation on the task so the AWS DMS task compares the source and targetrecords, and reports any mismatches.

Correct Answer: D

A Database Specialist is performing a proof of concept with Amazon Aurora using a small instance to confirm a simple database behavior. When loading a large dataset and creating the index, the Database Specialist encounters the following error message from Aurora:
ERROR: cloud not write block 7507718 of temporary file: No space left on device
What is the cause of this error and what should the Database Specialist do to resolve this issue?

1. A. The scaling of Aurora storage cannot catch up with the data loadin
2. B. The Database Specialist needs tomodify the workload to load the data slowly.
3. C. The scaling of Aurora storage cannot catch up with the data loadin
4. D. The Database Specialist needs toenable Aurora storage scaling.
5. E. The local storage used to store temporary tables is ful
6. F. The Database Specialist needs to scale up theinstance.
7. G. The local storage used to store temporary tables is ful
8. H. The Database Specialist needs to enable localstorage scaling.

Correct Answer: C