Quick Answer
Amazon ElastiCache for Redis is the correct choice because it delivers sub-millisecond latency session storage through an in-memory data store, perfectly matching the gaming company’s need for ephemeral player session data that can be lost on failure without impact. Redis excels here by supporting data structures like strings and hashes with TTL expiration, allowing transient data to automatically expire, which aligns with the requirement for speed over durability. On the AWS Certified Database Specialty DBS-C01 exam, this question tests your ability to distinguish between services optimized for low-latency caching versus durable databases; a common trap is choosing DynamoDB due to its fast performance, but DynamoDB offers persistent storage and is not designed for purely ephemeral, loss-tolerant workloads. Remember the memory tip: “Redis is for rapid, transient sessions—if it can vanish without a trace, Redis is the place.”
This DBS-C01 practice question tests your understanding of workload-specific database design. 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.
A gaming company needs a database to store player session data that is ephemeral and requires sub-millisecond latency. The data can be lost on failure without impact. Which service is best?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "best"
Why it matters: Signals that multiple options may be partially correct. Choose the option that most directly solves the exact problem described, not the one that sounds most complete.
Amazon DynamoDB
Why wrong: DynamoDB latency is in single-digit milliseconds, not sub-millisecond.
Amazon RDS for PostgreSQL
Why wrong: RDS has higher latency and is not ephemeral.
Amazon S3
Why wrong: S3 is object storage with higher latency, not suitable for real-time session data.
Amazon ElastiCache for Redis
ElastiCache Redis provides sub-millisecond latency and can be configured with no persistence.
Answer choices
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 best choice because it provides an in-memory data store with sub-millisecond latency, ideal for ephemeral player session data that can be lost on failure. Redis supports data structures like strings and hashes with TTL (time-to-live) expiration, perfectly matching the transient, low-latency requirement without needing durability.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
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 latency is in single-digit milliseconds, not sub-millisecond.
Amazon RDS for PostgreSQL
Why it's wrong here
RDS has higher latency and is not ephemeral.
Amazon S3
Why it's wrong here
S3 is object storage with higher latency, not suitable for real-time session data.
Amazon ElastiCache for Redis
Why this is correct
ElastiCache Redis provides sub-millisecond latency and can be configured with no persistence.
Clue confirmation
The clue word "best" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
The trap here is that candidates may choose DynamoDB (Option A) because it is a common choice for session data, but the question's explicit requirement for sub-millisecond latency and tolerance for data loss points to an in-memory cache like Redis, not a durable database.
Detailed technical explanation
Under the hood, ElastiCache for Redis stores all data in RAM, enabling sub-millisecond read/write operations via the Redis protocol (e.g., SET/GET commands). The TTL feature automatically evicts expired session keys, and the in-memory nature means data is lost on node failure unless persistence (RDB/AOF) is enabled—but the question explicitly allows data loss, making this ideal. In a real-world gaming scenario, Redis can handle millions of session updates per second with consistent single-digit microsecond latency, far exceeding DynamoDB's typical 1-10 ms p99 latency.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
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.
What to study next
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
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Practise DBS-C01 questions linked to Workload-Specific Database Design.
Practise DBS-C01 questions linked to Deployment and Migration.
Practise DBS-C01 questions linked to Management and Operations.
Practise DBS-C01 questions linked to Monitoring and Troubleshooting.
Practise DBS-C01 questions linked to Database Security.
Practise DBS-C01 questions linked to DBS-C01 fundamentals.
Practise DBS-C01 questions linked to DBS-C01 scenario.
Practise DBS-C01 questions linked to DBS-C01 troubleshooting.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Workload-Specific Database Design — This question tests Workload-Specific Database Design — Read the scenario before looking for a memorised answer..
The correct answer is: Amazon ElastiCache for Redis — Amazon ElastiCache for Redis is the best choice because it provides an in-memory data store with sub-millisecond latency, ideal for ephemeral player session data that can be lost on failure. Redis supports data structures like strings and hashes with TTL (time-to-live) expiration, perfectly matching the transient, low-latency requirement without needing durability.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Yes — watch for: "best". Signals that multiple options may be partially correct. Choose the option that most directly solves the exact problem described, not the one that sounds most complete.
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 →
Last reviewed: Jun 24, 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.