AWS Certified Developer – Associate (DVA-C02) — Question 482

In a move toward using microservices, a company’s management team has asked all development teams to build their services so that API requests depend only on that service’s data store. One team is building a Payments service which has its own database; the service needs data that originates in the Accounts database. Both are using Amazon DynamoDB.

What approach will result in the simplest, decoupled, and reliable method to get near-real time updates from the Accounts database?

Answer options

• A. Use AWS Glue to perform frequent ETL updates from the Accounts database to the Payments database.
• B. Use Amazon ElastiCache in Payments, with the cache updated by triggers in the Accounts database.
• C. Use Amazon Data Firehose to deliver all changes from the Accounts database to the Payments database.
• D. Use Amazon DynamoDB Streams to deliver all changes from the Accounts database to the Payments database.

Correct answer: D

Explanation

Amazon DynamoDB Streams captures a time-ordered sequence of item-level modifications in a table, making it the most native, reliable, and decoupled way to propagate near-real-time updates between DynamoDB tables. AWS Glue is designed for batch ETL rather than near-real-time synchronization, while using ElastiCache or Amazon Data Firehose introduces unnecessary architectural complexity for a direct DynamoDB-to-DynamoDB replication scenario.