[merk]

It could be something like the below, but remember that the query could be very specific and this one will only work for one thread and one post. You might need to do 2 queries to actually make it work for any other purpose.

[sql]
SELECT thread.*, post.*
FROM thread
LEFT JOIN post USING (threadid)
WHERE thread.threadid = <THREAD_ID>
ORDER BY post.dateline DESC
LIMIT 1
[/sql]