CREATE TABLE routes (rid NUMBER, dst_apid NUMBER, dst_ap CLOB, src_apid NUMBER, src_ap CLOB, alid NUMBER, airline CLOB, codeshare CLOB)
CREATE TABLE airports (apid NUMBER, name CLOB, city CLOB, country CLOB, x NUMBER, y NUMBER, elevation NUMBER, iata CLOB, icao CLOB)
CREATE TABLE airlines (alid NUMBER, name CLOB, iata CLOB, icao CLOB, callsign CLOB, country CLOB, active CLOB)

What is the number of cities in the United States with more than 3 airports?
SELECT city FROM airports WHERE country = 'United States' GROUP BY city HAVING COUNT(*) > 3
SELECT "city" FROM "airports" WHERE "country" = 'United States' GROUP BY "city" HAVING COUNT(*) > 3