Re: RMAN: data block restore

Matthias Hoys wrote:
> "hpuxrac" <johnbhurley_at_sbcglobal.net> wrote in message
> news:1122833131.224809.26030_at_g43g2000cwa.googlegroups.com...
> > EdwardNing (nospam) wrote:
> >> Hi, group, I am reading RMAN (9206) and have a question about data block
> >> level restore.
> >>
> >> First question is, how could I create a data block corruption for testing
> >> purpose?
> >>
> >> Second, if I restore only one block from older backups, what will happen
> >> to
> >> the data inside the database? I am a little bit confused here. Say if
> >> the
> >> data block contains data in a parent table, and I restored an older data
> >> block, which does not have the entry of this row any more, what happens
> >> to
> >> the child table entries which depends on this row?
> >>
> >> Thans for your help.
> >
> > To create block corruption (for testing purposes ONLY on a test system)
> > you have 2 choices that I am aware of that work for windows or unix
> > based systems.
> >
> > For windows, there are a bunch of free editors that can edit any block.
> > Use one of them to trash a block (just write binary ones to the whole
> > block for example).
> >
> > On unix or linux based systems you can again use a hex editor or use
> > the dd command to copy in a block of all 1's or 0's or whatever you
> > choose.
> >
> > You use the rman commands to detect and recover from block corruption.
> > Rman will recover the corrupted block and apply online redo entries to
> > bring the datablock to "what it should be". Child table entries in
> > other non corrupted blocks won't be affected at all.
> >
>
> On Unix, what if you open a datafile with vi and change some of the contents
> ? Never tried it lol.

May work ok depending on what kind of oracle environment you are running.

If raw dd is the recommended way to hose up your oracle database blocks. Received on Sun Jul 31 2005 - 15:34:28 CDT