这个貌似没有，我这里给你提供一个，也是网上的，我用了好使

create or replace function f_str_to_col(in_text varchar2,--String
                                                             fh      varchar2,--separator
                                                              n       number)  --No. of separator
                                        return varchar2 is
Result varchar2(4000);
begin
  if n > 1 then
    SELECT substr(in_text,

                  decode(instr(in_text, fh, n - 1, n - 1),
                         0,
                         0,
                         instr(in_text, fh, n - 1, n - 1) + 1),

                  decode(sign(instr(in_text, fh, n, n) -
                              instr(in_text, fh, n - 1, n - 1)),
                         1,
                         (instr(in_text, fh, n, n) -
                         instr(in_text, fh, n - 1, n - 1)) - 1,
                         -1,
                         length(in_text),
                         0,
                         0)

                  )
      into Result
      FROM dual;
  else
    select substr(in_text, 0, instr(in_text, fh, 1, 1) - 1) into Result from dual;
  end if;
  return(Result);
end f_str_to_col;