- A
Amazon DynamoDB
Why wrong: DynamoDB can work but introduces higher latency and cost for this simple use case.
- B
Amazon RDS for PostgreSQL
Why wrong: Relational database adds overhead and is not optimized for simple key-value lookups.
- C
Amazon Neptune
Why wrong: Neptune is a graph database, unsuitable for session data.
- D
Amazon ElastiCache for Redis
In-memory key-value store with sub-millisecond latency, ideal for session management.
Question 590 of 1,730
DBS-C01 Workload-Specific Database Design Practice Question
This DBS-C01 practice question tests your understanding of workload-specific database design. Match the stated requirement to the specific cloud service, access model, or configuration option — many options are valid in isolation but not for this scenario. 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.
A startup wants to store session data for a web application. Each session is small (under 1 KB) and accessed frequently with low latency. The data can be ephemeral and does not require complex queries. Which AWS database service is most suitable?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Amazon ElastiCache for Redis
Amazon ElastiCache for Redis is the most suitable choice because it is an in-memory data store that provides sub-millisecond latency for frequent reads and writes, ideal for ephemeral session data under 1 KB. Redis supports key-value storage with built-in time-to-live (TTL) expiration, which automatically removes stale sessions without additional application logic, and its simple data model avoids the overhead of complex queries.
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.
- ✗
Amazon DynamoDB
Why it's wrong here
DynamoDB can work but introduces higher latency and cost for this simple use case.
- ✗
Amazon RDS for PostgreSQL
Why it's wrong here
Relational database adds overhead and is not optimized for simple key-value lookups.
- ✗
Amazon Neptune
Why it's wrong here
Neptune is a graph database, unsuitable for session data.
- ✓
Amazon ElastiCache for Redis
Why this is correct
In-memory key-value store with sub-millisecond latency, ideal for session management.
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 often choose DynamoDB (Option A) because they associate it with 'NoSQL' and 'low latency,' but they overlook that ElastiCache for Redis is purpose-built for ephemeral, in-memory caching with even lower latency and automatic eviction, which is the optimal fit for session data.
Detailed technical explanation
How to think about this question
Under the hood, Redis stores all data in RAM, using a single-threaded event loop for atomic operations, which ensures consistent low-latency responses even under high concurrency. Its TTL mechanism is implemented via the EXPIRE command, which sets a key's lifetime in seconds; expired keys are lazily removed on access or periodically via a background scan, making it efficient for session management. In a real-world scenario, a startup could use ElastiCache with cluster mode disabled for simple session storage, or enable cluster mode for horizontal scaling if session volume grows beyond a single node's memory capacity.
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 media company stores terabytes of video archives that are accessed once a year for audit purposes. Moving these objects to a cold storage tier (Azure Archive, S3 Glacier, or Google Nearline) costs a fraction of hot storage. Questions like this test whether you understand storage tiers, access frequency tradeoffs, and retrieval latency requirements.
Quick reference
AWS S3 Storage Class Comparison
| Storage Class | Min Duration | Retrieval | Use Case |
|---|---|---|---|
| S3 Standard | None | Immediate | Frequently accessed data |
| S3 Standard-IA | 30 days | Immediate | Infrequent access, rapid retrieval |
| S3 One Zone-IA | 30 days | Immediate | Non-critical infrequent data |
| S3 Intelligent-Tiering | None | Immediate–hours | Unknown or changing access patterns |
| S3 Glacier Instant | 90 days | Milliseconds | Archive with instant retrieval |
| S3 Glacier Flexible | 90 days | Minutes–hours | Archive, flexible retrieval |
| S3 Glacier Deep Archive | 180 days | Hours | Long-term compliance archive |
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.
- →
Workload-Specific Database Design — study guide chapter
Learn the concepts, then practise the questions
- →
Workload-Specific Database Design practice questions
Targeted practice on this topic area only
- →
All DBS-C01 questions
1,730 questions across all exam domains
- →
AWS Certified Database Specialty DBS-C01 study guide
Full concept coverage aligned to exam objectives
- →
DBS-C01 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related DBS-C01 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Workload-Specific Database Design practice questions
Practise DBS-C01 questions linked to Workload-Specific Database Design.
Deployment and Migration practice questions
Practise DBS-C01 questions linked to Deployment and Migration.
Management and Operations practice questions
Practise DBS-C01 questions linked to Management and Operations.
Monitoring and Troubleshooting practice questions
Practise DBS-C01 questions linked to Monitoring and Troubleshooting.
Database Security practice questions
Practise DBS-C01 questions linked to Database Security.
DBS-C01 fundamentals practice questions
Practise DBS-C01 questions linked to DBS-C01 fundamentals.
DBS-C01 scenario practice questions
Practise DBS-C01 questions linked to DBS-C01 scenario.
DBS-C01 troubleshooting practice questions
Practise DBS-C01 questions linked to DBS-C01 troubleshooting.
Practice this exam
Start a free DBS-C01 practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this DBS-C01 question test?
Workload-Specific Database Design — This question tests Workload-Specific Database Design — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Amazon ElastiCache for Redis — Amazon ElastiCache for Redis is the most suitable choice because it is an in-memory data store that provides sub-millisecond latency for frequent reads and writes, ideal for ephemeral session data under 1 KB. Redis supports key-value storage with built-in time-to-live (TTL) expiration, which automatically removes stale sessions without additional application logic, and its simple data model avoids the overhead of complex queries.
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 →
Keep practising
More DBS-C01 practice questions
- A company is deploying a new application on Amazon RDS for PostgreSQL. The security policy requires that all data be enc…
- Match each AWS service to its primary purpose.
- A financial services company runs a production Amazon Aurora MySQL database cluster (1 writer, 2 readers) in us-east-1.…
- A company is designing a database for a global e-commerce platform that requires low-latency reads and writes from multi…
- A security auditor reviews the output of a DynamoDB table description command as shown in the exhibit. Which statement a…
- A company is migrating an on-premises Oracle database to Amazon RDS for Oracle. The database contains sensitive data tha…
Last reviewed: Jul 4, 2026
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.