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From Suresh Thalamati <suresh.thalam...@gmail.com>
Subject Re: [jira] Commented: (DERBY-239) Need a online backup feature that does not block update operations when online backup is in progress.
Date Tue, 01 Nov 2005 01:29:57 GMT
Øystein Grøvlen wrote:
>>>>>>"ST" == Suresh Thalamati <suresh.thalamati@gmail.com> writes:
>     ST> Hi Øystein,
>     ST> Thanks for reviewing the patch. My answers are in-line...
>     ST> Øystein Grøvlen (JIRA) wrote:

<snip ...>

>     ST> By using the catalog approach also backup can only throw a warning
>     ST> about the  deleted container. Once the user deletes a container file ,
>     ST> there is no way out, users can not even drop that table. I don't think
>     ST> making  backup  fail  forever   when  this  scenario  occurs  will  be
>     ST> acceptable to the users.
> I agree, but detecting in on backup, gives the user the option of
> recovering the table by restoring the previous bakcup.

I agree with you, notifying the user as early as possible about the 
missing files is a vey good idea. If there is no previous backup then 
detecting and stopping the backup is not a good idea either.
I belive  this is not common case scenario, this  improvements can
be added later,  once I get the online backup/restore to work.

<snip ..>

>     ST> 2)  Move  the backing  up  and  unlatching of  the  page  code to  the
>     ST> FileContainer.java.
>     ST> I have  not thought of  any other better  ways to do design  this, any
>     ST> ideas will be helpful.
> Could the backup code be in a separate class instead of part of
> RAFContainer?  It does not seem to use much of RAFContainer's internal
> state. 

   I think  backup code in Rafcontainer.java is ok. Purpose of the 
backup code there is to backup the container.  Backup needs to 
synchronize with the container file deletions and truncation. And also 
backup code is just couple of methods in this file, so it may not be 
worth creating yet another Class file.


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