with email_delpoints as
(select email_from, delivery_point_id, create_date lead_date
from (
select email_from, delivery_point_id, create_date, rank() over (partition by email_from order by create_date desc) as rnk
from email e
where  e.create_date >= '01-MAR-2017'
--and    e.create_date < '01-APR-2017'
and    e.email_type_id = 6
and    e.sec_user_login_source_id in (1,4)
and    e.delivery_point_id is not null) sub where rnk = 1)
select *
from   email_delpoints ed;