postgresql7.1
update ml_mailing_list_user_map
set subscribed_p = 'f',
unsubscription_date = current_timestamp
where list_id = :list_id
and user_id = :user_id
insert into ml_mailing_list_user_map
(list_id, user_id, subscribed_p, subscription_date)
values (:list_id, :user_id, 't', current_timestamp)
update ml_mailing_list_user_map
set subscribed_p = 't',
subscription_date = current_timestamp
where list_id = :list_id
and user_id = :user_id