DVA-C02 Development with AWS Services Practice Question
A developer is building a microservices application that processes event messages from multiple sources. The application requires at-least-once delivery, but message ordering is not important. Which Amazon SQS queue type should the developer use?
⚠ Common exam trap
Candidates often confuse the 'at-least-once' delivery requirement with the need for ordering, leading them to choose FIFO queues, but the question explicitly states ordering is not important, making Standard queues the correct and more performant choice.
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
✓
Standard queue
Amazon SQS Standard queues provide at-least-once delivery and best-effort ordering, making them ideal for microservices that can tolerate duplicate messages and do not require strict message sequencing. Since the application processes events from multiple sources and message ordering is not important, a Standard queue meets the requirements without the throughput limitations of FIFO queues.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Standard queue
Why this is correct
Standard queues are the default SQS queue type, designed for high throughput and best-effort ordering. They guarantee at-least-once message delivery, meaning a message might be delivered more than once, which requires consumers to be idempotent. This queue type is ideal for microservices where strict message ordering is not critical, and the application can handle occasional duplicates or out-of-order processing efficiently.
- ✗
FIFO queue
Why it's wrong here
FIFO (First-In, First-Out) queues provide strict message ordering and exactly-once processing, ensuring messages are delivered precisely once and in the order they were sent. While crucial for use cases requiring sequential processing, these guarantees come with lower throughput limits compared to Standard queues. For a general microservices application without explicit ordering requirements, the performance overhead of a FIFO queue is unnecessary and less optimal.
- ✗
Dead-letter queue
Why it's wrong here
A Dead-Letter Queue (DLQ) serves as a repository for messages that a source queue's consumers fail to process successfully after a specified number of retries. It is a critical component for error handling and debugging, allowing developers to inspect and reprocess problematic messages. However, a DLQ is a secondary queue configured with a primary queue, not the main queue type for initial message ingestion in a microservices architecture.
- ✗
Delay queue
Why it's wrong here
A delay queue is not a distinct queue type but rather a feature applied to either Standard or FIFO queues, making messages invisible for a specified duration. When a message is sent to a queue with a delay setting, it remains hidden from consumers for up to 15 minutes before becoming available. This functionality is useful for delaying the processing of messages, but it does not define the fundamental characteristics or primary purpose of the queue itself.
Go deeper
Related to this question
About these practice questions
One of 724 original DVA-C02 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 DVA-C02 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 DVA-C02 exam.