- A
Amazon ElastiCache for Redis for real-time queries, and Amazon OpenSearch Service for historical analytics.
Why wrong: ElastiCache is not designed for 10,000 writes per second of 1 KB events, and OpenSearch is not cost-effective for ad-hoc analytical queries on months of data.
- B
Amazon DynamoDB with DynamoDB Accelerator (DAX) for real-time queries, and Amazon S3 with Amazon Athena for historical analytics.
DynamoDB handles high write throughput, DAX provides sub-second reads, and S3 with Athena allows cost-effective ad-hoc queries on historical data.
- C
Amazon Redshift for both real-time and historical queries, using auto-scaling and materialized views.
Why wrong: Redshift is optimized for complex analytical queries but not for sub-second real-time queries on fast-changing data.
- D
Amazon RDS for PostgreSQL with read replicas for real-time queries, and Amazon Redshift for historical analytics.
Why wrong: RDS PostgreSQL cannot handle 10,000 writes per second, and read replicas add latency. Redshift is not needed if S3+Athena suffices.
Quick Answer
The correct combination is Amazon DynamoDB with DynamoDB Accelerator (DAX) for real-time queries and Amazon S3 with Athena for historical analytics. This architecture works because DAX acts as an in-memory cache that delivers sub-second read latency for the last hour of hot data, while S3 stores all historical time-series events cost-effectively, and Athena enables serverless ad-hoc SQL queries on that data without managing infrastructure. On the AWS Certified Database Specialty DBS-C01 exam, this question tests your ability to separate real-time and analytical workloads—a common pattern where you must avoid over-provisioning a single database. The trap is choosing Redshift for everything, but Redshift excels at complex analytics, not sub-second point lookups. Remember the memory tip: “Hot in DAX, cold in S3—Athena queries for history, DAX for speed.”
DBS-C01 Workload-Specific Database Design Practice Question
This DBS-C01 practice question tests your understanding of workload-specific database design. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. 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 is building a real-time analytics dashboard on AWS. The data arrives as time-series events from IoT devices at a rate of 10,000 writes per second. Each event is approximately 1 KB. The dashboard requires sub-second query latency for the last hour of data and must support ad-hoc analytical queries on historical data spanning months. The team needs to design a cost-effective database solution. Which combination of AWS services should be used?
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 DynamoDB with DynamoDB Accelerator (DAX) for real-time queries, and Amazon S3 with Amazon Athena for historical analytics.
Option A is correct because DynamoDB Accelerator (DAX) provides sub-second read latency for hot data, while Amazon S3 with Athena supports ad-hoc queries on historical data cost-effectively. Option B is wrong because Amazon Redshift is optimized for complex analytics but not for sub-second real-time queries. Option C is wrong because ElastiCache for Redis alone cannot handle the high write throughput and is not designed for analytics. Option D is wrong because Amazon RDS for PostgreSQL with read replicas is not designed for 10,000 writes per second and querying historical data would be expensive and slow.
Key principle: NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
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 ElastiCache for Redis for real-time queries, and Amazon OpenSearch Service for historical analytics.
Why it's wrong here
ElastiCache is not designed for 10,000 writes per second of 1 KB events, and OpenSearch is not cost-effective for ad-hoc analytical queries on months of data.
- ✓
Amazon DynamoDB with DynamoDB Accelerator (DAX) for real-time queries, and Amazon S3 with Amazon Athena for historical analytics.
- ✗
Amazon Redshift for both real-time and historical queries, using auto-scaling and materialized views.
Why it's wrong here
Redshift is optimized for complex analytical queries but not for sub-second real-time queries on fast-changing data.
- ✗
Amazon RDS for PostgreSQL with read replicas for real-time queries, and Amazon Redshift for historical analytics.
Why it's wrong here
RDS PostgreSQL cannot handle 10,000 writes per second, and read replicas add latency. Redshift is not needed if S3+Athena suffices.
Common exam traps
Common exam trap: NAT rules depend on direction and matching traffic
NAT is not only about the public address. The inside/outside interface roles and the ACL or rule that matches traffic are just as important.
Detailed technical explanation
How to think about this question
NAT questions usually test address translation, overload/PAT behaviour, static mappings and whether the right traffic is being translated. Read the interface direction and address terms carefully.
KKey Concepts to Remember
- Static NAT maps one inside address to one outside address.
- PAT allows many inside hosts to share one public address using ports.
- Inside local and inside global describe the private and translated addresses.
- NAT ACLs identify traffic for translation, not always security filtering.
TExam Day Tips
- Identify inside and outside interfaces first.
- Check whether the scenario needs static NAT, dynamic NAT or PAT.
- Do not confuse NAT matching ACLs with normal packet-filtering intent.
Key takeaway
NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
Real-world example
How this comes up in practice
A startup's cloud architect reviews their monthly bill and notices costs are higher than expected for a long-running batch job. Switching from on-demand instances to Reserved Instances — or using Spot/Preemptible VMs — can reduce compute costs by up to 72 %. Questions like this test whether you understand the tradeoffs between commitment, flexibility, and cost across cloud pricing models.
What to study next
Got this wrong? Here's your next step.
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related DBS-C01 NAT questions on configuration and troubleshooting.
- →
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 — Static NAT maps one inside address to one outside address..
What is the correct answer to this question?
The correct answer is: Amazon DynamoDB with DynamoDB Accelerator (DAX) for real-time queries, and Amazon S3 with Amazon Athena for historical analytics. — Option A is correct because DynamoDB Accelerator (DAX) provides sub-second read latency for hot data, while Amazon S3 with Athena supports ad-hoc queries on historical data cost-effectively. Option B is wrong because Amazon Redshift is optimized for complex analytics but not for sub-second real-time queries. Option C is wrong because ElastiCache for Redis alone cannot handle the high write throughput and is not designed for analytics. Option D is wrong because Amazon RDS for PostgreSQL with read replicas is not designed for 10,000 writes per second and querying historical data would be expensive and slow.
What should I do if I get this DBS-C01 question wrong?
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related DBS-C01 NAT questions on configuration and troubleshooting.
What is the key concept behind this question?
Static NAT maps one inside address to one outside address.
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 20, 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.