An order system receives events and uses a Lambda function to write each order into a database. During traffic spikes, the database sometimes throttles, and Lambda retries lead to occasional message loss in the event flow. The team wants buffering, automatic retries, and a way to isolate messages that repeatedly fail so they can be inspected later. What design change best meets this need?

Send events directly from EventBridge to Lambda without any queue to simplify the flow.

Direct invocation provides less buffering and no dedicated dead-letter handling for persistent failures.

Use SNS fan-out to multiple Lambda functions, but keep no retry logic and no DLQ.

SNS fan-out doesn’t provide the same buffering model as SQS, and without a DLQ you lose failed event traceability.

Store events in an S3 bucket and trigger Lambda immediately after each upload, without using DLQs.

S3 event notifications can trigger Lambda, but they do not provide DLQ-based isolation and standard queue retries the same way.

What does this SAA-C03 question test?

Static NAT maps one inside address to one outside address.

What is the correct answer to this question?

The correct answer is: Use Amazon SQS as a buffer between the event source and Lambda, with an SQS dead-letter queue (DLQ). — Using SQS as a decoupling buffer directly addresses bursts and throttling. SQS stores incoming events so Lambda does not have to process them immediately at the event source rate. SQS enables retries automatically through visibility timeouts, and when processing fails repeatedly, an SQS dead-letter queue (DLQ) captures the problematic messages for later inspection. This improves reliability and prevents message loss during transient database throttling events. Why others are wrong: Direct EventBridge-to-Lambda reduces buffering and makes it harder to isolate repeatedly failing messages. SNS fan-out without DLQ does not provide an equivalent buffering and failure isolation pattern. Using S3 event triggers can work for event-driven workflows, but it lacks a native DLQ mechanism and the standard retry semantics that SQS provides in this scenario.

What should I do if I get this SAA-C03 question wrong?

Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.