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)
CREATE TABLE routes (rid NUMBER, dst_apid NUMBER, dst_ap CLOB, src_apid NUMBER, src_ap CLOB, alid NUMBER, airline CLOB, codeshare CLOB)

Find the name and city of the airport which is the source for the most number of flight routes.
SELECT T1.name, T1.city, T2.src_apid FROM airports AS T1 JOIN routes AS T2 ON T1.apid = T2.src_apid GROUP BY T2.src_apid ORDER BY COUNT(*) DESC LIMIT 1
SELECT "T1"."name", "T1"."city", "T2"."src_apid" FROM "airports" "T1" JOIN "routes" "T2" ON "T1"."apid" = "T2"."src_apid" GROUP BY "T2"."src_apid" ORDER BY COUNT(*) DESC FETCH FIRST 1 ROWS ONLY