Order By with Group By

Question

Is there an efficient way to do an order by and group by so that you get a specific item from each group (from the order by).

//This is the best way i have come up with.
SELECT D.*
FROM (
    SELECT *
    FROM devices
    ORDER BY time
) AS D
GROUP BY D.location

Answer 1

This worked for me

SELECT *
FROM (SELECT *
      FROM col
      ORDER BY col DESC,date DESC)a
GROUP BY col

Answer 2

SELECT *
FROM devices
GROUP BY D.location
ORDER BY time --ASC or DESC default is ASC i believe

No need for sub-queries