Oracle PL-SQL function to convert bytes into KB, MB and so on

oracle_format_size

create or replace function format_size(p_size IN NUMBER) 
return VARCHAR2
IS
  v_i number;
  type array_t is varray(3) of varchar2(10);
  v_array array_t := array_t(' Bytes', ' KB', ' MB');
BEGIN
  v_i := floor(log(1024, p_size));
  return to_char(round(p_size/power(1024, v_i), 2))||v_array(v_i+1);
END;