Welcome to your interview.
The question is on your right: Schema Design and Caching. Take a moment with it first.
Talk your thinking through with me if you like - when you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes). Discussion and graded submissions share your five interviewer interactions, so spend them well.
What is your experience with database schema design and caching strategies for large datasets at Vamstar?