Advanced MySQL query to get range of latest records with same id and different subids -


i have table called sensorvalue this:

station_id   sensor_id   timestamp            value ---------------------------------------------------------- 1            1           2013-09-04 12:00:00  12.2 1            2           2013-09-04 12:00:00  13.1 1            3           2013-09-04 12:00:00  13.2 1            1           2013-09-04 12:05:00  12.1 1            2           2013-09-04 12:05:00  14.1 1            3           2013-09-04 12:05:00  13.2 1            1           2013-09-04 12:10:00  12.5 1            2           2013-09-04 12:10:00  13.3 1            3           2013-09-04 12:10:00  14.1

i need mysql query gets latest values of 3 sensors of station station_id 1. wonder if possible 1 mysql statement.

i've managed data out of table, not in efficient way. first select different sensors station 1 , afterthat call mysql select statement foreach sensor. of stations have on 10 sensors, approach need @ least 11 mysql statements data out of database.

i include in 1 mysql statement. possible? , how?

retrieve latest reading sensors on stations.

select s.*   (select station_id, sensor_id, max(timestamp) max_timestamp           sensorvalue          group station_id, sensor_id        ) m   join sensorvalue s     on s.station_id = m.station_id    , s.sensor_id  = m.sensor_id    , s.timestamp  = m.max_timestamp

to limit specific station.

select s.*   (select station_id, sensor_id, max(timestamp) max_timestamp           sensorvalue          station_id = 1          group station_id, sensor_id        ) m   join sensorvalue s     on s.station_id = m.station_id    , s.sensor_id  = m.sensor_id    , s.timestamp  = m.max_timestamp

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