SQL> ;
  1  with t(ID, CLASS, NAME, CCODE) as (
  2  select 123 ,2 ,null     , 'op' from dual union all
  3  select 123 ,1 ,'Marina' , null from dual union all
  4  select 123 ,3 ,'Alex'   , null from dual
  5  )
  6  select
  7    id
  8   ,max(name )keep(dense_rank last order by nvl2(name ,t.class,null) nulls first) name
  9   ,max(ccode)keep(dense_rank last order by nvl2(ccode,t.class,null) nulls first) ccode
 10  from t
 11* group by id
SQL> /

        ID NAME   CC
---------- ------ --
       123 Alex   op