Welcome to your interview.
The question is on your right: Handling Nulls Before Analysis. 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 how you would handle missing or NULL values in a PostgreSQL dataset before starting analysis. Focus on a practical workflow: identify missingness, decide whether to keep, filter, or replace NULLs, and explain how simple SQL tools support those choices.
COALESCE and CASE WHEN appropriately