CREATE TABLE station (bikes_available NUMBER, station_id VARCHAR2, id VARCHAR2, city VARCHAR2)
CREATE TABLE status (bikes_available NUMBER, station_id VARCHAR2, id VARCHAR2, city VARCHAR2)

What is the average bike availability in stations that are not located in Palo Alto?
SELECT AVG(bikes_available) FROM status WHERE NOT station_id IN (SELECT id FROM station WHERE city = "Palo Alto")
SELECT AVG("bikes_available") FROM "status" WHERE NOT "station_id" IN (SELECT "id" FROM "station" WHERE "Palo Alto" = "city")