The answer is the expected scalability and throughput requirements. This is correct because the decision between Amazon RDS and DynamoDB fundamentally depends on whether your application needs complex relational queries with joins and aggregations, which RDS supports via SQL, or predictable, low-latency key-value and document lookups, which DynamoDB excels at with its distributed, single-digit millisecond performance. On the AWS Certified Database Specialty DBS-C01 exam, this question tests your ability to map data access patterns to the appropriate service, often appearing in scenario-based questions where a trap is choosing based on cost or familiarity rather than query complexity. A common memory tip is to think "RDS for relationships, DynamoDB for speed and scale"—if your app needs ad-hoc filters and flexible joins, lean toward RDS; if it demands high throughput with simple, single-key reads, choose DynamoDB.
DBS-C01 Deployment and Migration Practice Question
This DBS-C01 practice question tests your understanding of deployment and migration. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
Which THREE factors should be considered when choosing between Amazon RDS and Amazon DynamoDB for a new application? (Choose THREE.)
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The query patterns and access methods required by the application.
Option C is correct because the choice between Amazon RDS (relational) and DynamoDB (NoSQL) hinges on the application's data access patterns. RDS supports complex SQL queries with joins, aggregations, and secondary indexes, while DynamoDB is optimized for key-value and document queries with predictable, low-latency access patterns. If the application requires flexible querying with ad-hoc filters, RDS is appropriate; if it needs high-throughput, single-key lookups or simple query patterns, DynamoDB is better suited.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
The query patterns and access methods required by the application.
Why this is correct
RDS supports SQL queries, while DynamoDB is NoSQL with key-value and document queries.
Related concept
Read the scenario before looking for a memorised answer.
✓
The need for complex transactions and joins.
Why this is correct
RDS supports complex transactions and joins; DynamoDB has limited transaction support.
Related concept
Read the scenario before looking for a memorised answer.
✓
The expected scalability and throughput requirements.
Why this is correct
DynamoDB is designed for horizontal scaling; RDS scales vertically and with read replicas.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates assume encryption at rest or multi-AZ HA are exclusive to one service, but both RDS and DynamoDB fully support these features, making them irrelevant for choosing between the two.
Detailed technical explanation
How to think about this question
Under the hood, RDS uses a traditional relational engine (e.g., InnoDB for MySQL) with ACID transactions and multi-statement support via BEGIN/COMMIT, while DynamoDB uses a distributed hash table with eventual consistency and limited transactional APIs (TransactWriteItems, TransactGetItems) that support up to 25 items per transaction. In a real-world scenario, an e-commerce order system requiring complex joins between orders, customers, and inventory would favor RDS, whereas a session store or leaderboard requiring millions of writes per second with simple key lookups would favor DynamoDB.
KKey Concepts to Remember
Read the scenario before looking for a memorised answer.
Find the constraint that changes the correct option.
Eliminate answers that are true in general but not in this case.
TExam Day Tips
→Watch for words such as best, first, most likely and least administrative effort.
→Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A company's IT admin needs to give a contractor read-only access to production logs without sharing account credentials. Using role-based access control (RBAC) and temporary scoped permissions — not a permanent shared password — is the correct pattern. Questions like this test whether you can apply least-privilege access across cloud identity services.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Deployment and Migration — This question tests Deployment and Migration — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: The query patterns and access methods required by the application. — Option C is correct because the choice between Amazon RDS (relational) and DynamoDB (NoSQL) hinges on the application's data access patterns. RDS supports complex SQL queries with joins, aggregations, and secondary indexes, while DynamoDB is optimized for key-value and document queries with predictable, low-latency access patterns. If the application requires flexible querying with ad-hoc filters, RDS is appropriate; if it needs high-throughput, single-key lookups or simple query patterns, DynamoDB is better suited.
What should I do if I get this DBS-C01 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
This DBS-C01 practice question is part of Courseiva's free Amazon Web Services certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the DBS-C01 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.