Oracle: Create LOBs of arbitrary length

create or replace function tq84_create_clob(len integer) return clob
   authid definer
as
   lob           clob;
   remaining_len integer := len;
begin

   lob := lpad('*', least(remaining_len, 4000), '*');
   remaining_len := remaining_len - 4000;

   while remaining_len > 0 loop
      dbms_lob.writeappend(lob, least(remaining_len, 4000), lpad('*', 4000, '*'));
      remaining_len := remaining_len - 4000;
   end loop;

   return lob;
end tq84_create_clob;
/

create table tq84_lob_len (
   len       integer,
   lob       clob
);


begin
   insert into tq84_lob_len values (  1234, tq84_create_clob(  1234));
   insert into tq84_lob_len values (999999, tq84_create_clob(999999));
   insert into tq84_lob_len values (     0, tq84_create_clob(     0));
   insert into tq84_lob_len values (  null, tq84_create_clob(  null));
   commit;
end;
/

select
   len,
   length(lob),
   dbms_lob.getlength(lob)
from
   tq84_lob_len;

drop table tq84_lob_len;