How can I select rows with most recent timestamp for each key value?

Question

I have a table of sensor data. Each row has a sensor id, a timestamp, and other fields. I want to select a single row with latest timestamp for each sensor, including some o

Answer 1

WITH SensorTimes As (
   SELECT sensorID, MAX(timestamp) "LastReading"
   FROM sensorTable
   GROUP BY sensorID
)
SELECT s.sensorID,s.timestamp,s.sensorField1,s.sensorField2 
FROM sensorTable s
INNER JOIN SensorTimes t on s.sensorID = t.sensorID and s.timestamp = t.LastReading