rockset-query-braking.sql

/* Grouping events emitted in last 5 seconds by vehicleId and getting the time of the oldest event in this group */
WITH vehicles_in_last_5_seconds AS (
    SELECT
        vehicleinfo.vehicleId,
        vehicleinfo._event_time,
        vehicleinfo.speed
    from
        commons.vehicleinfo
    WHERE
        vehicleinfo._event_time > CURRENT_TIMESTAMP() - SECONDS(5)
),
older_sample_time_for_vehicles as (
    SELECT
        MIN(vehicles_in_last_5_seconds._event_time) as min_time,
        vehicles_in_last_5_seconds.vehicleId
    FROM
        vehicles_in_last_5_seconds
    GROUP BY
        vehicles_in_last_5_seconds.vehicleId
),
older_sample_speed_for_vehicles AS (
    SELECT
        vehicles_in_last_5_seconds.speed,
        vehicles_in_last_5_seconds.vehicleId
    FROM
        older_sample_time_for_vehicles,
        vehicles_in_last_5_seconds
    where
        vehicles_in_last_5_seconds._event_time = older_sample_time_for_vehicles.min_time
        and vehicles_in_last_5_seconds.vehicleId = older_sample_time_for_vehicles.vehicleId
),
latest_sample_time_for_vehicles as (
    SELECT
        MAX(vehicles_in_last_5_seconds._event_time) as max_time,
        vehicles_in_last_5_seconds.vehicleId
    FROM
        vehicles_in_last_5_seconds
    GROUP BY
        vehicles_in_last_5_seconds.vehicleId
),
latest_sample_speed_for_vehicles AS (
    SELECT
        vehicles_in_last_5_seconds.speed,
        vehicles_in_last_5_seconds.vehicleId
    FROM
        latest_sample_time_for_vehicles,
        vehicles_in_last_5_seconds
    where
        vehicles_in_last_5_seconds._event_time = latest_sample_time_for_vehicles.max_time
        and vehicles_in_last_5_seconds.vehicleId = latest_sample_time_for_vehicles.vehicleId
)

SELECT
    latest_sample_speed_for_vehicles.speed,
    older_sample_speed_for_vehicles.speed,
    older_sample_speed_for_vehicles.vehicleId
from
    older_sample_speed_for_vehicles, latest_sample_speed_for_vehicles
WHERE
    older_sample_speed_for_vehicles.vehicleId = latest_sample_speed_for_vehicles.vehicleId
    AND latest_sample_speed_for_vehicles.speed < older_sample_speed_for_vehicles.speed - 20