Your question is Database Architecture Trade-offs. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
Describe the trade-offs you have encountered when choosing between different database architectures for a high-concurrency application.
Discuss how you would evaluate relational, NoSQL, distributed SQL, cache, and event-streaming options for an ML system with online feature access and feedback ingestion. Explain the workload characteristics, consistency requirements, failure modes, capacity questions, and operational signals you would use to make and validate the decision.