Exam AWS Certified Database - Specialty topic 1 question 29 discussion

"To ensure that your data was migrated accurately from the source to the target, we highly recommend that you use data validation." https://docs.aws.amazon.com/dms/latest/userguide/CHAP_BestPractices.html Answer is D.

DMS supports the validation between source and target data. But SCT does not support it.

table metrics of the AWS DMS can be verified manully for DMS task. There is no mechanism which provided an automated for reading these metric and providing confirmation if every thing went well. If you are working 100+ tables then DMS Data Validation is the only option. D is best fit

D would run select queries on source & target to compare rows, so some load B is also good candidate, rather better but it needed "The data validation option in the DMS task has to be activated before DMS " You can find individual table metrics on the Table statistics tab for each individual task. These metrics include these numbers: Rows loaded during the full load. Inserts, updates, and deletes since the task started. DDL operations since the task started. B. 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. D. Enable AWS DMS data validation on the task so the AWS DMS task compares the source and target records, and reports any mismatches.

D for data validation

https://docs.aws.amazon.com/dms/latest/userguide/CHAP_Validating.html During data validation, AWS DMS compares each row in the source with its corresponding row at the target, verifies the rows contain the same data, and reports any mismatches. To accomplish this AWS DMS issues appropriate queries to retrieve the data. Note that these queries will consume additional resources at the source and target as well as additional network resources. So Answer should be B

'The migration should have a negligible effect on the source database's performance.' I believe answer should be 'B' Table metrics You can find individual table metrics on the Table statistics tab for each individual task. These metrics include these numbers: Rows loaded during the full load. Inserts, updates, and deletes since the task started. DDL operations since the task started.

D is the correct answer