plsql中利用函数将一个逗号分隔字符串转义返回单个的列

1.传进去一个字符串，类似于'123,456';
CREATE OR REPLACE FUNCTION GET_STRING_TAB (v_str in varchar2) return table_string pipelined as
  v_new_str varchar2(8000);
begin
  if v_str is null then
    pipe row(-1);
  else
    v_new_str:=v_str;
    while 1=1 loop
      if instr(v_new_str,',')=0 then
        pipe row(v_new_str);
        exit;
      else
        pipe row(substr(v_new_str,1,instr(v_new_str,',')-1));
        v_new_str:=substr(v_new_str,instr(v_new_str,',')+1);
      end if;
    end loop;
  end if;
  return;
end;
2 select * from table(get_string_tab('100002236,100002236'))
结果：   COLUMN_VALUE
1 100002236
2 100002236