CREATE TABLE employee (eid NUMBER, name CLOB, salary NUMBER)
CREATE TABLE aircraft (aid NUMBER, name CLOB, distance NUMBER)
CREATE TABLE certificate (eid NUMBER, aid NUMBER)
CREATE TABLE flight (flno NUMBER, origin CLOB, destination CLOB, distance NUMBER, departure_date TIME, arrival_date TIME, price NUMBER, aid NUMBER)

Show flight number for all flights with more than 2000 distance.
SELECT flno FROM flight WHERE distance > 2000
SELECT "flno" FROM "flight" WHERE "distance" > 2000