chat_messages(message_id, sender_id, sent_at)

Return the five busiest senders in the 30 days up to and including 2026-09-30, which means from 2026-09-01 onward.

Return sender_id and message_count, most messages first, breaking ties by the lower sender_id, and at most five rows.

Tables

chat_messages

message_id  sender_id  sent_at
----------  ---------  -------------------
1           1          2026-09-02 10:00:00
2           1          2026-09-03 10:00:00
3           1          2026-09-04 10:00:00
4           2          2026-09-02 10:00:00
5           2          2026-09-03 10:00:00
6           3          2026-09-05 10:00:00
7           3          2026-09-06 10:00:00
8           4          2026-09-07 10:00:00
... 6 more row(s)

Expected result

sender_id  message_count
---------  -------------
1          3
2          2
3          2
4          1
5          1