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

List the main industry with highest total market value and its number of companies.
SELECT main_industry, COUNT(*) FROM company GROUP BY main_industry ORDER BY SUM(market_value) DESC LIMIT 1
SELECT "main_industry", COUNT(*) FROM "company" GROUP BY "main_industry" ORDER BY SUM("market_value") DESC FETCH FIRST 1 ROWS ONLY