update forums_messages
set last_poster = :to_user_id
where last_poster = :from_user_id
update forums_messages
set user_id = :to_user_id
where user_id = :from_user_id
select message_id, subject
from forums_messages
where user_id = :user_id
select message_id, subject
from forums_messages
where last_poster = :user_id