DBS-C01 Workload-Specific Database Design Practice Question
A company is building a real-time leaderboard for a gaming application. The leaderboard must update scores within seconds and support queries for top players and individual ranks. Which database design is most appropriate?
⚠ Common exam trap
Candidates might gravitate toward Redis (Option B) because of its native sorted set support, which is highly efficient for leaderboards. However, DynamoDB can also serve this use case with a global secondary index on score, allowing queries for top players and individual ranks with low latency, and it offers a fully managed serverless experience that scales automatically.
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 a global secondary index on score
Amazon DynamoDB with a global secondary index (GSI) on score is the most appropriate design because it supports real-time updates and low-latency queries for both top players (via query on the GSI with ScanIndexForward=false and Limit) and individual ranks (via efficient key lookups). DynamoDB's fully managed, serverless architecture ensures sub-second response times at any scale, which is critical for a gaming leaderboard that must update scores within seconds.
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 S3 with Range GET requests
Why it's wrong here
S3 is not meant for real-time transactional updates.
- ✗
Amazon ElastiCache for Redis with sorted sets
Why it's wrong here
Redis is in-memory and not designed for durable persistence as a primary database.
- ✓
Amazon DynamoDB with a global secondary index on score
Why this is correct
DynamoDB GSI enables efficient querying of top scores and rank lookups.
- ✗
Amazon RDS for PostgreSQL with ORDER BY and LIMIT
Why it's wrong here
Relational databases struggle with high write throughput and large leaderboard queries.
Quick reference
Cloud Service Model Comparison
| Model | You Manage | Provider Manages | Examples |
|---|---|---|---|
| IaaS | OS, runtime, apps, data | Hardware, hypervisor, networking | EC2, Azure VMs, GCP Compute Engine |
| PaaS | Apps and data | OS, runtime, middleware, hardware | Elastic Beanstalk, Azure App Service |
| SaaS | Data and settings only | Everything else | Microsoft 365, Salesforce, Workday |
| FaaS / Serverless | Function code only | Infra, scaling, runtime | Lambda, Azure Functions, Cloud Run |
| CaaS | Containers and apps | Kubernetes, OS, hardware | EKS, AKS, GKE |
Go deeper
Related to this question
About these practice questions
This DBS-C01 question is part of Courseiva's 1,663-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
Same concept, more angles
1 more way this is tested on DBS-C01
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. A startup is building a real-time leaderboard for a gaming application. The data is highly dynamic with frequent updates and requires single-digit millisecond latency. Which database is most suitable?
easy- A.Amazon Neptune
- B.Amazon Redshift
- ✓ C.Amazon DynamoDB
- D.Amazon RDS for PostgreSQL
Why C: Amazon DynamoDB is the most suitable choice because it is a fully managed NoSQL key-value and document database that delivers single-digit millisecond latency at any scale, making it ideal for real-time leaderboards with high-frequency updates. Its DAX (DynamoDB Accelerator) caching layer can further reduce read latency to microseconds, while its auto-scaling and on-demand capacity modes handle the highly dynamic workload without downtime.
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
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.