--
-- acs_objects_last_mod_update_tr/0
--
create or replace function acs_objects_last_mod_update_tr(
  
) returns trigger as $$

begin
  if new.last_modified is null then
     new.last_modified := old.last_modified;
  elsif new.last_modified = old.last_modified then
     new.last_modified := now();
  end if;
  return new;
end;$$ language plpgsql;