Převod dne v roce na datum, kdy některé formáty data mají v oracle DDDYYYY a některé DDDYYYY

Co třeba tohle:

with demo (data_date) as
     ( select 1072015 from dual union all
       select 12017 from dual union all
       select 612014 from dual union all
       select 672013 from dual union all
       select 72017 from dual union all
       select 1112018 from dual )
select data_date
     , to_char(data_date,'0000000')
     , to_date(to_char(data_date,'0000000'),'DDDYYYY') as data_date_converted
from   demo