with tmp(id, t1, t2, t3, t4, n1, n2, n3, n4, n5, dt) as ( 
select 1,null,'aa',null,null,null,null,null,null,5 , '2020-08-20 12:00:01'  from dual union all  
select 1,'bb',null,'cc',null,null,20,null,null,null, '2020-08-20 12:00:02' from dual union all 
select 1,null,null,null,'dd',null,70,25,null,null, '2020-08-20 12:00:03'    from dual union all
select 1,null,null,'OK','OK',3,null,null,null,null, '2020-08-20 12:00:04'   from dual )
select id,
max(id) keep (dense_rank last order by nvl2(id, 1, 0), dt) as id,
max(t1) keep (dense_rank last order by nvl2(t1, 1, 0), dt) as t1,
max(t2) keep (dense_rank last order by nvl2(t2, 1, 0), dt) as t2,
max(t3) keep (dense_rank last order by nvl2(t3, 1, 0), dt) as t3,
max(t4) keep (dense_rank last order by nvl2(t4, 1, 0), dt) as t4,
max(n1) keep (dense_rank last order by nvl2(n1, 1, 0), dt) as n1,
max(n2) keep (dense_rank last order by nvl2(n2, 1, 0), dt) as n2,
max(n3) keep (dense_rank last order by nvl2(n3, 1, 0), dt) as n3,
max(n4) keep (dense_rank last order by nvl2(n4, 1, 0), dt) as n4,
max(n5) keep (dense_rank last order by nvl2(n5, 1, 0), dt) as n5,
max(dt) dt
From tmp
group by id;

        ID       ID_1 T1 T2 T3 T4         N1         N2         N3 N4         N5 DT                 
---------- ---------- -- -- -- -- ---------- ---------- ---------- -- ---------- -------------------
         1          1 bb aa OK OK          3         70         25             5 2020-08-20 12:00:04
1 row selected.

max(id) keep (dense_rank last order by nvl2(id, 1, 0), dt) as id,

with tmp(id, t1, t2, t3, t4, n1, n2, n3, n4, n5, dt) as ( 
select 1,null,'aa',null,null,null,null,null,null,5 , to_date('2020-08-20 12:00:01', 'yyyy-mm-dd hh24:mi:ss') from dual union all  
select 1,'bb',null,'cc',null,null,20,null,null,null, to_date('2020-08-20 12:00:02', 'yyyy-mm-dd hh24:mi:ss') from dual union all 
select 1,null,null,null,'dd',null,70,25,null,null,   to_date('2020-08-20 12:00:03', 'yyyy-mm-dd hh24:mi:ss') from dual union all
select 1,null,null,'OK','OK',3,null,null,null,null,  to_date('2020-08-20 12:00:04', 'yyyy-mm-dd hh24:mi:ss') from dual )
select *
from
   (select id,    
    last_value(t1 ignore nulls) over (partition by id order by dt) as t1,
    last_value(t2 ignore nulls) over (partition by id order by dt) as t2,
    last_value(t3 ignore nulls) over (partition by id order by dt) as t3,
    last_value(t4 ignore nulls) over (partition by id order by dt) as t4,
    last_value(n1 ignore nulls) over (partition by id order by dt) as n1,
    last_value(n2 ignore nulls) over (partition by id order by dt) as n2,
    last_value(n3 ignore nulls) over (partition by id order by dt) as n3,
    last_value(n4 ignore nulls) over (partition by id order by dt) as n4,
    last_value(n5 ignore nulls) over (partition by id order by dt) as n5,    
    max(dt)                     over (partition by id)             as dt,
    row_number()                over (partition by id order by dt) as rn,
    count(*)                    over (partition by id)             as cnt
    From tmp
   )
where rn = cnt;

rows between unbounded preceding and unbounded following