UPDATE   address ad
SET      (area_id, street_id)      =
           <COMPLICATED QUERY>
WHERE    EXISTS
           <result from COMPLICATED QUERY>

UPDATE   address ad
SET      (area_id, street_id)      =
          (SELECT new_area_id, new_street_id
           FROM <COMPLICATED JOINS>
           WHERE ad.ID = local.ID)
WHERE    EXISTS
          (SELECT 1
           FROM <COMPLICATED JOINS>
           WHERE ad.ID = local.ID)

merge into address a
      using <COMPLICATED JOINS> local
      on ad.ID = local.ID
when matched then update set area_id=new_area_id, street_id=new_street_id
when not matched then insert (id) values (local.id) where 1=2
/