Re: easy query (?)

Alice Erickson <erickson_at_denebola.biostat.wisc.edu> a écrit dans l'article
> I would like the final temperature reading for each city at the end of
 the
> day.
>
> EX.
> City Time Temp
> Boston 15:00 30
> Boston 24:00 10
> Phoenix 5:00 70
> Phoenix 6:00 72
>
> The resulting set should be
> Boston 24:00 10
> Phoenix 6:00 72
>
> but oracle will now allow you to use
>
> select city, max(temp), time from table
> group by city
>
> (as you are now also getting an aggregate of time)
>

Hello,

You can try :

SELECT a.city, a.time, a.temp
FROM table a
WHERE a.time = (SELECT max(b.time)

                         FROM table b
                         WHERE b.city = a.city)

May this help you.

-- 
BrunoThomas    bthomas_at_teaser.fr