Re: Database Recovery

On Mon, 19 Aug 2002 05:38:00 +1000, "Howard J. Rogers" <howardjr2000_at_yahoo.com.au> wrote:

>
><abc_at_iom.com> wrote in message
>news:3d5fd811.325087451_at_news.sf.sbcglobal.net...
>>
>> Ok, here's a scenario:
>>
>> There is a database--call it "MyDB" on server "A" Server A is Oracle
>> 9i, Release 2 MyDb has never been backed up.
>> However, all the files pertaining to that database (control, data,
>> redo) have been copied to a safe place in another folder on that
>> server.
>
>You mean, you have a backup.
>
>>
>> Disaster strikes. The database server software installation is
>> hopelessly screwed. No hope in hell of getting it reinstalled on that
>> server.
>>
>> Fortunately, there's Server B! It has Oracle 9i Release 2 as well.
>> In fact, it's the exact same installation as Server A--only this
>> server works. The only instance running on Server B is some test db.
>> I want Server B to "See" my original database, "MyDB". I copy the
>> original physical files from the original database in question over to
>> this new Server B.
>>
>
>You mean, you do a restore onto a second machine.
>
>
>> Now the question: How do I get Server B to recognize this new
>> database?
>
>You start an instance. If these machines are NT, you create a service first
>(and a password file) by running oradim. If this is a unix box, you set your
>environment variables (such as ORACLE_SID), modify your init.ora so that it
>points to the location of the controlfile, and issue the startup MOUNT
>command. It has to be 'MOUNT', because your controlfile needs adjusting -it
>thinks the datafiles are where they used to be on your first machine. You
>sit there issuing 'alter database rename file 'x' to 'y'; comands so that it
>becomes aware of their locations on the new machine.
>
>You then either try 'alter database open', or you issue that 'recover
>database' command. It depends on how your backup was taken (whether it was
>done hot or cold) and whether you have archives available.
>
>>I'm sure it has something to do with RECOVER, RMAN, etc.
>> But from reading the docs, all these commands assume that I have an
>> instance up and running for this database I want to recover. I don't
>> yet , of course, because Server B doesn't know that this MyDB even
>> exists yet.
>>
>> In short, how do I go from having raw Database files on a server to an
>> actual running instance?
>>
>> For those of you who are familiar with SQL Server 2000, this is like
>> the Attach/Detach command. In this case I would ATTACH this database
>> and bring it on-line. But as you know, SQL Server and Oracle are two
>> different animals.
>
>They certainly are: what you call a database in SQL Server 2000 is merely a
>schema (or perhaps a tablespace) in Oracle. So, before anyone else tells you
>in less friendly terms, let me advise against trying to make comparisons and
>point-to-point matches between the two products. They are about as similar
>as two completely dissimilar things in a pod.
>
>You *ought* to know how to start an instance... it's pretty fundamental. But
>if all you've ever used are GUI tools such as OEM, all the work needed to
>make that happen has been hidden from you.
>
>But to receive advice on how to do it, you need to be (a) more concise and
>(b) more precise. All this talk about "machine A" and "machine B" isn't very
>helpful. Whenever you post here, include specific Oracle version and
>operating system version. Instructions vary wildly depending on both.
>
>If you are on Windows, you are going to need to know about oradim. Hi thee
>to http://technet.oracle.com and become a registered member, and start
>reading the doco. on it. Open a DOS window, and type oradim /? at the
>command prompt.
>
>Post back with the specifics, and we can go through it.
>
>Regards
>HJR
>
>>
>> Any help appreciated.
>
>

Well, thanks for the tips. I belive I'm thoroughly hosed, however, but it was an interesting learning experience. I worked through all the commands such as ALTER DATABASE RENAME...., even did a RECOVER DATABASE. But in the end, it gave me an ORA-01092: oracle instance terminated. Disconnection forced" message.

It was only test data so no big deal. However, it's alway a good learning experience to have a potentially hosed database and try to recover it.

FYI, I'm running Windows 2K, Oracle 9i, release 9.2

Live and learn.... Received on Sun Aug 18 2002 - 17:48:05 CDT