Arthernan wrote:
> On Apr 23, 5:39 pm, Arthernan <arther..._at_hotmail.com> wrote:
>> On Apr 16, 4:30 pm, DA Morgan <damor..._at_psoug.org> wrote:
>>
>>
>>
>>> NetComrade wrote:
>>>> 2 questions
>>>> a) can someone point to a source that descrives how theflashbackarea
>>>> actually works
>>>> b) did anyone ever had to 'flash back' a database in production? I
>>>> really can't think of a scenario where it would be useful (since it
>>>> forces you to lose
>>>> .......
>>>> We run Oracle 9iR2,10gR1/2 on RH4/RH3 and Solaris 10 (Sparc)
>>>> remove NSPAM to email
>>> FlashbackDatabase is one of the most useful and valuable features
>>> added in 10g.
>>> Very simply I use it with guaranteed restore points any time we are:
>>> 1. Patching applications
>>> 2. Patching the database
>>> 3. Batch loading
>>> Flashbackis not useful because you use it a lot any more than a
>>> fire extinguisher is valuable because you use it a lot. They are
>>> invaluable because they are available for use when required.
>>> As to how theflashbackarea works I would suggest that this is a
>>> topic too large for a single paragraph in a usenet group and that
>>> you read the docs athttp://tahiti.oracle.com.
>>> --
>>> Daniel A. Morgan
>>> University of Washington
>>> damor..._at_x.washington.edu
>>> (replace x with u to respond)
>>> Puget Sound Oracle Users Groupwww.psoug.org
>> I have been looking at adding flashback-like functionality to our
>> company system. I can see the benefit from a DBA perspective.
>>
>> In our case I am most interested on giving this functionality to the
>> end users. But I am hesitant because it seems to require a great deal
>> of DB configuration and it makes the task of looking at history very
>> different. For example I did not see anywhere where you could do a
>> query like this.
>>
>> Select Employee_name, Salary, DateAdded, DateRemoved from Employee
>> where DateAdded<point_in_time and (DateRemoved>point_in_time or
>> DateRemoved is null)
>>
>> Now I don't pretend for flashback to work MY way. But for this to work
>> for my end users I would need to show them history at the record
>> level. So they can then pick a sinlge record/transaction and recreate
>> it they need it, or maybe just research changes already made.
>>
>> Does anybody have experience using Oracle Flashback in a similar way?
>
> Before I get abused for not reading the manual, I'd like to say that I
> did see this
>
> Select Employee_name, Salary from Employee
> as of timestamp point_in_time;
>
> But this leaves out the columns DateAdded and DateRemoved. Whatever
> pseudocolumns that could exist with the time of the changes are very
> important for the end user research.
>
> Of course, the alternative is to use triggers of to improve the
> application logic, which is what I currently do. One benefit of
> writing your own flashback logic is that it is your own and possibly
> not dependent on oracle propietary features.
There is little evidence, from what you wrote, that you read the
manual. Your statement about "leaves out" is incorrect. Take a look
at the Flashback Transaction Query demo in Morgan's Library at
www.psoug.org.
--
Daniel A. Morgan
University of Washington
damorgan_at_x.washington.edu
(replace x with u to respond)
Puget Sound Oracle Users Group
www.psoug.org
Received on Mon Apr 23 2007 - 22:50:02 CDT
