AWS Certified Database – Specialty — Question 331

A company's database specialist implements an AWS Database Migration Service (AWS DMS) task for change data capture (CDC) to replicate data from an on- premises Oracle database to Amazon S3. When usage of the company's application increases, the database specialist notices multiple hours of latency with the
CDC.
Which solutions will reduce this latency? (Choose two.)

Answer options

• A. Configure the DMS task to run in full large binary object (LOB) mode.
• B. Configure the DMS task to run in limited large binary object (LOB) mode.
• C. Create a Multi-AZ replication instance.
• D. Load tables in parallel by creating multiple replication instances for sets of tables that participate in common transactions.
• E. Replicate tables in parallel by creating multiple DMS tasks for sets of tables that do not participate in common transactions.

Correct answer: B, E

Explanation

Limited LOB mode is significantly faster than Full LOB mode because AWS DMS pre-allocates memory and loads LOB data in bulk, reducing transactional latency during high-volume CDC. Additionally, splitting tables that do not participate in common transactions into multiple DMS tasks allows for parallel processing without compromising transactional integrity. Creating multiple tasks for tables that do share transactions (Option D) would break transactional consistency, and Multi-AZ (Option C) is designed for high availability rather than performance improvement.