Exam AWS Certified Solutions Architect - Associate SAA-C03 topic 1 question 10 discussion

B because FIFO is made for that specific purpose

Should be B because SQS FIFO queue guarantees message order.

The requirement is to process orders in the order they are received. SNS (A): no ordering guarantees. SQS Standard (D): scalable but does not preserve order. API Gateway Authorizer (C): handles auth, not ordering. SQS FIFO (B): guarantees strict ordering and exactly-once processing. ✅ Correct Answer: B. API Gateway → SQS FIFO Queue → Lambda check reason why the answer B is Correct >>>https://shorturl.at/b5khA

Use Amazon API Gateway → SQS FIFO Queue → Lambda to ensure ordered, reliable processing of incoming orders — meeting the ecommerce application's needs.

keywords: orders should be process in the order when it receives B is correct answer, use API gateway intergation with FIFO SQS invoke lambda function for processing order A; SNS + lambda: SNS does not grant order messages to subscribers C: is not the correct one since we wanted to process the message in order so we do not have to block D: using standard queue does not grant the order of messages being sent

B SQS FIFO is made for that

FIFO make sure to send the data exactly in the same order

B is the only solution that guarantees message order.

Has to be FIFO queue for this requirement

SQS FIFO as if want to maintain order of messages recieved to order of messages sent. It is like QUEUE data structutre in DSA

SQS FIFO gurantees message order.

Explanation: FIFO Queues: Amazon SQS FIFO queues are specifically designed to maintain the order of messages. This ensures that messages are processed in the exact sequence they were sent, which is crucial for order processing in an e-commerce application. Why other options are less suitable: A. Amazon SNS: SNS is a publish-subscribe service. It doesn't guarantee message order. C. API Gateway Authorizer: Authorizers are used for authentication and authorization, not for managing message order. D. Amazon SQS Standard Queue: Standard SQS queues do not guarantee message order.

Standard queues ensure at-least-once message delivery, but due to the highly distributed architecture, more than one copy of a message might be delivered, and messages may occasionally arrive out of order.

AnswerB - SQS FIFO queues ensure that messages are processed in the order they are received, which perfectly matches the requirement of maintaining order.

A lot of answers seem to not match the most voted. i'm confused which to follow.

Explanation: To ensure that orders are processed in the order that they are received, the best solution is to use an Amazon SQS FIFO (First-In-First-Out) queue. This type of queue maintains the exact order in which messages are sent and received. In this case, the application can send information about new orders to an Amazon API Gateway REST API, which can then use an API Gateway integration to send a message to an Amazon SQS FIFO queue for processing. The queue can then be configured to invoke an AWS Lambda function to perform the necessary processing on each order. This ensures that orders are processed in the exact order in which they are received.

Keywords: - Orders are processed in the order that they are received. A: Incorrect - SNS just for notification like send email, SMS. It don't retain the data in the queue and it's used pub-sub pattern. B: Correct - SQS FIFO will help message process in order. FIFO -> first in first out. C: Incorrect - with this solution we will create blocker app not good app =)) D: Incorrect - SQS standard don't guarantee the order.