Table schema:
CREATE TABLE district (headquartered_city VARCHAR, district_id VARCHAR); CREATE TABLE store_district (store_id VARCHAR, district_id VARCHAR); CREATE TABLE store (store_id VARCHAR)

Question: Find the city with the most number of stores.
SQL: SELECT t3.headquartered_city FROM store AS t1 JOIN store_district AS t2 ON t1.store_id = t2.store_id JOIN district AS t3 ON t2.district_id = t3.district_id GROUP BY t3.headquartered_city ORDER BY COUNT(*) DESC LIMIT 1