Sorting users by latest entry in posts table, how to query?

Question

PostgreSQL

Good afternoon.
There are tables
users - contains users.
messages - contains a bunch of messages, where there is createdAt
We need to get users and sort them in chronological order by messages.
How can this be done without requests? Maybe there are some specialized aggregate functions

Answer 1

select u.* from users as u
inner join messages as m
  on u.id = m.user_id
group by u.id
order by max(m.createdAt);