Welcome to your interview.
The question is on your right: SQL Indexes, Joins, and Performance. 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.
Explain what an index is in SQL, how joins work, and how you avoid blocking or performance issues in SQL queries.