Database Software

Hi

I know that when I start the database the scn of controlfile,datafile headers and redologs
shoud be same.

I can compare scn of datafiles from v$datafile_header
Control file from v$datafile
redolog from v$log

For example:

sys@XE> select CHECKPOINT_CHANGE# from v$datafile;

CHECKPOINT_CHANGE#
------------------
4344269
4344269
4344269
4344269


sys@XE> select first_Change# from v$log;

FIRST_CHANGE#
-------------
4341385
4341016



My database is up at the moment and above confirms that redolog scn is behind than controlfile and datafile.

What I want to ask is,
When I shutdown the database and restore old redologs and create a controlfile with noresetlogs option
It fails with:
ORA-01229: data file 4 is inconsistent with logs.

How can oracle understand if the current online redologs are consistent or not?
As I showed above, the redo scn is already behind while the db is up.
It should compare something else..