Write SQL to sum city population by name
Company: NVIDIA
Role: Software Engineer
Category: Software Engineering Fundamentals
Difficulty: easy
Interview Round: Technical Screen
You have four relational tables:
- country(country_id, name)
- state(state_id, country_id, name)
- city(city_id, state_id, name)
- zip(zip_code, city_id, population)
Task A: Given a city name (e.g., :city_name), write SQL to return the total population for that city, where population is stored in the zip table (sum across all ZIP codes belonging to the city).
Clarify how you would handle the case where multiple cities share the same name in different states/countries.
Quick Answer: Assesses SQL proficiency in relational joins and aggregation by asking for a total population computed from ZIP-level data and evaluates reasoning about duplicate entity names.