Re: RMAN: data block restore

"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. Received on Sun Jul 31 2005 - 14:49:57 CDT