CREATE TABLE aircraft (aid DECIMAL, name VARCHAR, distance DECIMAL)
CREATE TABLE certificate (eid DECIMAL, aid DECIMAL)
CREATE TABLE employee (eid DECIMAL, name VARCHAR, salary DECIMAL)
CREATE TABLE flight (flno DECIMAL, origin VARCHAR, destination VARCHAR, distance DECIMAL, departure_date DATE, arrival_date DATE, price DECIMAL, aid DECIMAL)

A bar chart showing the number of flights with price higher than 300 for each destination city.
SELECT destination, COUNT(destination) FROM flight WHERE price > 300 GROUP BY destination
SELECT "destination", COUNT("destination") FROM "flight" WHERE "price" > 300 GROUP BY "destination"