Oracle md5函数

create or replace function fn_md5(input_string VARCHAR2) return varchar2 IS
  raw_input RAW(128) := UTL_RAW.CAST_TO_RAW(input_string);
  decrypted_raw RAW(2048);
  error_in_input_buffer_length EXCEPTION;
BEGIN
  sys.dbms_obfuscation_toolkit.MD5(input    => raw_input,
                                   checksum => decrypted_raw);
  return lower(rawtohex(decrypted_raw));
END;