CREATE TABLE gas_station (station_id DECIMAL, open_year DECIMAL, location TEXT, manager_name TEXT, vice_manager_name TEXT, representative_name TEXT)
CREATE TABLE company (company_id DECIMAL, rank DECIMAL, company TEXT, headquarters TEXT, main_industry TEXT, sales_billion DECIMAL, profits_billion DECIMAL, assets_billion DECIMAL, market_value DECIMAL)
CREATE TABLE station_company (station_id DECIMAL, company_id DECIMAL, rank_of_the_year DECIMAL)

Show the manager name with most number of gas stations opened after 2000.
SELECT manager_name FROM gas_station WHERE open_year > 2000 GROUP BY manager_name ORDER BY COUNT(*) DESC LIMIT 1
SELECT "manager_name" FROM "gas_station" WHERE "open_year" > 2000 GROUP BY "manager_name" ORDER BY COUNT(*) DESC NULLS LAST LIMIT 1