Hi all, The situation: there are users in one table, and their access statistics in the other. Now I want to find users whose last access time was more than one month ago. As I've only had to write quite simple queries involving no sub-selects so far, I'd like to ask your opinion if this one scales at all or not.
SELECT u.login,last_use_time FROM users u JOIN (SELECT user_id, MAX(stop_time) AS last_use_time FROM stats GROUP BY user_id) AS s ON (u.id=s.user_id) WHERE status='3' AND next_plan_id IS NULL AND last_use_time < now() - interval '1 month' ORDER BY last_use_time; It seems to do the job, but how good is it in the long run? Any way I could tweak it? Thanks. ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend