Re: Hot Backup referenced external data

Hi jake: good questions. No, I think RMAN is an excellent utility. But I'd be using it because (a) the scripting language means that what works can be preserved, and protected behind the usual Oracle security mechanisms, (b) the fact that hot backups don't generate block-level backups, and thus the redo sub-system is not overly stressed, (c) recoveries become relatively simple affairs 'restore database - recover database' -I've seen too many restores stuffed up by failure to remember precisely what gets restored etc etc and (d)the fact that it's an Oracle utilitiy means it understands the concept of an Oracle block -and can report on any corruptions straight away (no need to remember to dbverify the results). You've only got to recall some of the posts here a few weeks back about 'three weeks of backup turns out to have included corrupt data files' to realise how important that little feature is.

I think the incremental possibilities come in around point (e). It can make all the difference between achieving a backup in the available maintenance window, and not.

I confess to having been utterly intimidated by the syntax from Hell with which RMAN is blessed (cursed?) in my early days with it. But that's just another language to learn, and given enough time, it's not *that* bad, with hindsight. I therefore recommend RMAN with conviction these days. Indeed, just last month, for the first time, one of my students did the entire Backup and Recovery workshop using nothing but RMAN. I was somewhat gobsmacked, but also deeply impressed, and persuaded that this (or something like it) ought to be the way of the future as regards backup and recovery.

Regards
HJR

--
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Opinions expressed are my own, and not those of Oracle Corporation
Oracle DBA Resources:               http://www.geocities.com/howardjr2000
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"Jake" <jjstrauss_at_yahoo.com> wrote in message
news:T%wQ5.13583$3u4.67355_at_e420r-sjo2.usenetserver.com...


> > I mentioned earlier.  Unless you are talking huge amounts of data, the

> > incremental backup feature is not the first one that springs to mind as

 a


> > reason for moving to RMAN, however.

>

> Howard, what is your first reason for moving to RMAN, or are you saying

 you


> prefer not to use RMAN?

>

> --

> Jake

> "Howard J. Rogers" <howardjr_at_www.com> wrote in message

> news:3a111d39$1_at_news.iprimus.com.au...

> > I'm slightly confused about what you are after, but here goes for

> > nothing....

> >

> > 1. How can we best backup data associated with a hot backup?

> >

> > I *really* don't understand this question.  A hot backup is a backup of

 the


> > data files associated with a database.  You want to backup a backup?  If

 you


> > mean, 'how do you do hot backups', the short answer is: do it a

 tablespace


> > at a time, issue the command 'alter tablespace blah begin backup; take a

> > host copy of the data files associated with that tablespace; when the

 copy


> > has finished, issue the command 'alter tablespace blah end backup'.  You

> > then move on to the next tablespace and so on, until all tablespaces

 have


> > been processed.  Full instructions are contained (amongst other places)

 in


> > my backup and recovery document, available on my website.

> >

> > 2. I think you then ask how (or whether) you can just backup the extra

> > column that has been added to a table.  Short answer is, you can't.

 Even


> > using RMAN's incremental backup feature, since that is row-level

 sensitive


> > to data changes, not column-sensitive.

> >

> > 3.  Yes, you can 'parse the data' from your archives, provided you have

> > 8.1.5 or above -the feature is called Log Miner (also 'parses data' from

> > on-line archive logs).  Anything earlier than 8.1.5, and you'll have to

 find


> > a third-party product that does the deed (and I don't know of any off

 hand).


> >

> > 4. 'Can we read incremental RMAN data'?  No, but (rather fortunately)

 RMAN


> > can.  If you mean, 'can RMAN do incremental backups', the answer is yes,

 as


> > I mentioned earlier.  Unless you are talking huge amounts of data, the

> > incremental backup feature is not the first one that springs to mind as

 a


> > reason for moving to RMAN, however.

> >

> > Not sure whether you are entirely familiar with backup and recovery

 concepts


> > and techniques.  L=ike Isay, go to my site, find the Backup and Recovery

> > course page, and download my small document there -and then get back to

 me


> > with any questions you may have.

> >

> > Regards

> > HJR

> > --

>

> --------------------------------------------------------------------------

> -

> > Opinions expressed are my own, and not those of Oracle Corporation

> > Oracle DBA Resources:

 http://www.geocities.com/howardjr2000


>

> --------------------------------------------------------------------------

> -

> >

> >

> > <dickweisinger_at_my-deja.com> wrote in message

> > news:8uqq5f$e1p$1_at_nnrp1.deja.com...

> > > Hi,

> > > Can you please help me?

> > > How can we best backup data associated with a hot

> > > backup?

> > > We have a table that references volume and file

> > > data.  As part of the hot backup, we want to do

> > > an incremental backup of all files that are newly

> > > referenced in the incremental hot database backup.

> > > (Someone added a column to the table with path to

> > > a file.)

> > > How can we best do this?  If we keep an

> > > ARCHIVELOG, can we parse the data from that

> > > file?  We may move to RMan in the near future --

> > > can we read incremental RMan data?

> > > Thanks

> > >

> > >

> > >

> > >

> > > Sent via Deja.com http://www.deja.com/

> > > Before you buy.

> >

> >

> >

>

>

>

>