Marco,
> Is there a way to obtain this records by performing one
> single query and not by making for each city something like
> "SELECT city,date FROM table WHERE city='London' AND date>'2002-07-19
> 15:39:15+00' ORDER BY date ASC LIMIT 1;"?
Close. Try:
SELECT city, MAX("date") as last_date
FROM table
WHERE "date" > $date
GROUP BY city
ORDER BY city
Though as an aggregate query, this will be slow on large tables.
--
-Josh Berkus
Aglio Database Solutions
San Francisco