CREATE TABLE station (id NUMBER, network_name CLOB, services CLOB, local_authority CLOB)
CREATE TABLE train (id NUMBER, train_number NUMBER, name CLOB, origin CLOB, destination CLOB, time CLOB, interval CLOB)
CREATE TABLE weekly_weather (station_id NUMBER, day_of_week CLOB, high_temperature NUMBER, low_temperature NUMBER, precipitation NUMBER, wind_speed_mph NUMBER)
CREATE TABLE route (train_id NUMBER, station_id NUMBER)

What is the average high temperature for each day of week?
SELECT AVG(high_temperature), day_of_week FROM weekly_weather GROUP BY day_of_week
SELECT AVG("high_temperature"), "day_of_week" FROM "weekly_weather" GROUP BY "day_of_week"