begin
insert into pref_ban2 select
id,
first_name,
last_name,
city,
last_ip
from pref_users where id=_id;
update pref_ban2 set reason=_reason where id=_id;
It's not the answer to your query, but why don't you do the above in a single statement?
If you can't see the forest for the trees,
Cut the trees and you'll see there is no forest.
