What is the percentage of trips that started in San Jose and durations were longer than 800 seconds?
percentage of trips = DIVIDE(COUNT(duration>800), COUNT(duration)) as percentage; San Jose refers to city = 'San Jose'; duration>800;
SELECT CAST(SUM(CASE WHEN T1.duration > 800 THEN 1 ELSE 0 END) AS REAL) * 100 / COUNT(T1.id) FROM trip AS T1 INNER JOIN station AS T2 ON T2.name = T1.start_station_name WHERE T2.city = 'San Jose'