Re: Restoring & recovering in NOARCHIVELOG

miotromailcarlos_at_netscape.net (Carlos) wrote in message news:<1de5ebe7.0307250226.22aa87e7_at_posting.google.com>...
> Hi all.
>
> We are working with Oracle 8.1.6 on Win NT in a production environment
> (don't blame me, It's heritage). The Database archiving mode is
> NOARCHIVELOG (again don't blame me). We do whole database backups
> daily al the end of the day (It's not a 24/7 DB). Due to requisites,
> we must be able to restore the status that the DB had at the beginning
> of the day (start) in order to reprocess (by external processes) all
> the activity of the day if necessary (this is easily done by restoring
> the last-night backup). But I'm wondering about recovering the DB if a
> HW problem occurs. Here is where my question comes out: If we use redo
> log files large enough to hold all the redo activities of a whole day
> we could not only restore the 'last-night cold backup' in order to
> reprocess, but recover the DB status to the instant before a HW
> failure as well by using the redo log files to roll forward.
> Am I right?

Besides what everyone else posted, what you propose puts even more extreme requirements than usual for the hardware that holds the redo logs. This is a really bad idea - others who have tried it have gone for a couple of years just fine, then BAM! discovered that even the most well-guaranteed zero-defect self-correcting buzzword-defying eternity-MTBF disks (or controllers!) can have problems.

Oracle's brilliance is in a design that can recover from many of the real-world screwups. What many people forget is that there are hardware issues that need to be taken into account that often aren't. For an older primer, see

http://metalink.oracle.com/cgi-bin/cr/getfile_cr.cgi?219092
http://metalink.oracle.com/cgi-bin/cr/getfile_cr.cgi?219091
http://metalink.oracle.com/cgi-bin/cr/getfile_cr.cgi?268502

jg

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