Re: backup without archivelog mode

Archivelog mode simply means that you can guarantee recoverability of all transactions. If you can guarantee recoverability by some other mechanism, then no, you don't need archivelog mode.

By that, I mean that these nightly loads must be coming from some source. If you can back that source up, and are prepared to repeat a nightly load if something happens to the database, who cares about archives?! A lot of sites, for example, will use SQL Loader to load millions of records from a text file. Since the text file can be burnt to CD, or put on tape, the load could be repeated if ever there was trouble on the database.

But: You can never, ever make a copy of any database file whilst the database is running, without that copy being internally inconsistent. And only archive logs guarantee that you can make an internally inconsistent datafile consistent. So: your choice. If you can repeat the loads, and don't mind doing so, don't bother with archives. But then all backups will require that you shut your database down before making a backup. And since you mention a weekend shutdown window, it's sounding as though you will need to sign up to perhaps repeating up to 6 or 7 nights'-worth of loads in the event of trouble (ie, you'd restore from the cold backup you took last weekend, and therefore have to repeat that entire weeks' loads).

If you want to take hot backups (which your use of the 'alter tablespace Florence begin backup' command suggests you want to do) then you will absolutely, positively have to be in archivelog mode. There is no exception to the rule that hot files cannot simply be copied. It matters not the slightest that no-one is doing anything but selects. *Oracle* will be doing things that cause the all-important SCNs to increment at unexpected intervals -at which point, you wouldn't be able to use the hot-copied files.

If your database is up when you take backups, regardless of what it's doing, it's a hot backup. You must behave as though it were a hot backup. And hot backups require archivelog mode.

If that's a storage pain, do cold backups once a week, and be prepared to repeat data loads.

The choice is entirely yours.

Regards
HJR

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"obakesan" <pellicle_at_hotmail.com> wrote in message
news:9baa2b9f.0203222306.388fb025_at_posting.google.com...


> HiYa

>

> if I have a database that is more like a datawarehouse in that it gets

> load files loaded into it nightly, but no other transactions take

> place

> that involve the update or insert of data during working hours, can I

> back this up with simply copying the datafiles, control files ...?

>

> I thought that there is no point in making archive redo logs as really

> all that will happen between sqlloads is some complex selects using

> packaged procedures, nothing that is transation oriented.

>

> If I copy the database files is there any meaning in issuing an

> alter tablespace boing_said_zebedee begin backup; command? will this

> be needed to gurantee consistency (in case a load is timed at the same

> point

> as the backup)? Is there any point in archiving redologs in this

> situation.

>

> Also I was thinking of a weekend down and full cold backup. As there

> will be no data loaded in this period, and no users on it either.

>

>

> thanks for your time