Re: How to apply archive logs on an cold backup

From: Howard J. Rogers <hjr_at_dizwell.com>
Date: Thu, 02 Sep 2004 13:52:40 -0700
Message-ID: <4136fb94$0$16193$afc38c87@news.optusnet.com.au>

Steve wrote:

> Howard J. Rogers wrote:

>> Bob Jones wrote:
>>
>> [snip]
>>
>>

>>>I don't see how the database would be vulnerable to media failure. At
>>>what point?

>>
>>
>> Immediately he issues the 'alter database open resetlogs' command, which
>> your version of the recovery command requires him to do.
>>
>> A media failure of any sort after that time cannot be recovered from,
>> except by doing exceedingly complex steps which are prone to be gotten
>> wrong.
>>

> I'm sorry Howard. Although 99.99% of your advice is absolutely spot on, > this is nothing of the sort.

To which bit do you take exception Steve?

I merely wrote something that is 100% factual, and no personal opinion involved. A resetlogs operation renders your database extremely vulnerable to further failure.

To counter that, you *have* to take a backup immediately after the database is recovered. That will require a cold backup if you want to minimise the risks. And that's expensive downtime.

The vulnerability to a second failure; and the excessive downtime needed to minimise it are why "voluntary" (ie, unnecessary) resetlogs are sensibly best avoided. (And one of the reasons why things like Log Miner and Flashback were invented -they allow you to reverse user errors *without* having to embark on an operation that must end in a resetlogs).

Now you can disagree with those facts if you want, but I can't see how.

HJR Received on Thu Sep 02 2004 - 15:52:40 CDT