"Dave Hau" <davehau_nospam_123_at_nospam_netscape.net> wrote in message
news:3F31895E.3060805_at_nospam_netscape.net...
>
>
> R.B wrote:
> > I had a situation where a database (9.2.0.3) which is running in archive
log
> > mode had to be restored (by restoring of the Unix files) from the
previous
> > night's cpio backup and the archive logs NOT applied i.e work was lost.
> >
> > Before I opened the database I ran 'archive log list' and found the
'Next
> > log sequence to archive' and moved it (12496) and all subsequent logs to
> > another location and then opened the database as below:
> >
> >
> > SQL> archive log list
> > Database log mode Archive Mode
> > Automatic archival Enabled
> > Archive destination /arch/FBSP
> > Oldest online log sequence 12494
> > Next log sequence to archive 12496
> > Current log sequence 12496
> >
> > (moved 12496 and subsequent logs)
> >
> > SQL> alter database open;
> >
> > Database altered.
> >
> > SQL> alter system checkpoint;
> >
> > System altered.
> >
> > SQL> alter system switch logfile;
> >
> > System altered.
> >
> > The database came up and is running
> >
> > My questions is
> >
> > Shutting down the database does appear to perform an archivelog switch
but I
> > assume it checkpoints the database so that the save represents the
> > 'complete' database save at that point in time. If this is the case then
> > won't the archive logs be out of sync with the database and therefore
would
> > be of no further use, since data has been written to the database but
not
> > the archivelogs.
>
> All a checkpoint does is to roll forward the database to a particular
> SCN according to redo log entries. It doesn't remove anything from the
> redo log, even after the data has been rolled forward. It only reads
> from the redo logs. In particular, it won't cause the redo logs to be
> out of sync with the data, or create any gap. So I guess I'm not fully
> understanding what you were trying to say.
>
> Cheers,
> Dave
>
Dave - you have answered my question. I thought that a checkpoint cleared
out the redo log entries as well as rolling forward the db - thanks
Received on Thu Aug 07 2003 - 06:01:59 CDT
