DEA-C01 Data Store Management Practice Question
A company needs to store JSON documents that are frequently read and written by a web application. The data must be highly available and durable across multiple Availability Zones. Which AWS database service meets these requirements?
⚠ Common exam trap
It's easy for candidates to confuse Amazon S3's high durability and availability with database capabilities, overlooking that S3 is an object store with higher latency and no native query support, while DynamoDB is purpose-built for low-latency, high-throughput document storage with ACID transactions via DynamoDB Transactions.
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
Amazon DynamoDB is a fully managed NoSQL key-value and document database that provides single-digit millisecond performance at any scale. It stores JSON documents natively, supports frequent reads and writes, and offers built-in high availability and durability by automatically replicating data across multiple Availability Zones (AZs) in an AWS Region. This makes it the ideal choice for the described web application workload.
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 RDS for PostgreSQL
Why it's wrong here
RDS for PostgreSQL stores JSON in relational tables, not as native document objects, and its Multi-AZ standby is passive, so it cannot serve the frequent read/write document workload the stem describes. It would suit transactional relational data needing ACID guarantees, not schema-flexible JSON documents.
- ✗
Amazon S3
Why it's wrong here
S3 is object storage, not a database; it lacks database features like transactions.
- ✓
Amazon DynamoDB
Why this is correct
DynamoDB is a fully managed NoSQL store holding JSON as native items, replicating synchronously across multiple Availability Zones for durability and high availability. Its key-value and document model suits frequent reads and writes from a web application without schema migrations.
- ✗
Amazon ElastiCache for Redis
Why it's wrong here
ElastiCache for Redis is an in-memory cache, not a durable JSON document store; it lacks multi-AZ persistence guarantees for primary data. It is tempting because it delivers sub-millisecond reads for session or cache workloads, where losing the dataset on failure is acceptable.
Go deeper
Related to this question
About these practice questions
One of 1,321 original DEA-C01 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This DEA-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 DEA-C01 exam.