What is the city_code of the city that the most students live in?
CREATE TABLE STUDENT (city_code VARCHAR)
SELECT city_code FROM STUDENT GROUP BY city_code ORDER BY COUNT(*) DESC LIMIT 1
### Context: CREATE TABLE STUDENT (city_code VARCHAR) ### Question: What is the city_code of the city that the most students live in? ### Answer: SELECT city_code FROM STUDENT GROUP BY city_code ORDER BY COUNT(*) DESC LIMIT 1