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From Suresh Thalamati <suresh.thalam...@gmail.com>
Subject Re: [PATCH] increasinng the possible log file id's from 2^22 -1 to 2^33 -1 (derby-101)
Date Wed, 18 May 2005 19:02:29 GMT
It's actually a good question David,  I  also heard of   other database 
which has this requirement.   In derby
users  are not requied to shutdown the datbase before doing  upgrade/ 
downgrade , I think is is to make 
Derby Zero-Admin database.   Any changes to the  logging system  also 
have  to  handle
upgrade/downgrade issues.

Thanks
-suresht

David Van Couvering wrote:

> Sorry, perhaps a dumb question here  -- I'm still learning how Derby 
> works.  If someone wants to downgrade from revision N+1 to revision N, 
> wouldn't they normally shut down the database prior to downgrade, in 
> which case the data gets checkpointed and the log files wouldn't be 
> needed?
>
> Thanks,
>
> David
>
> Mike Matrigali wrote:
>
>> I am looking at committing this.  The changes look good to me, but I
>> believe there are upgrade issues to handle.
>>
>> For a hard upgrade either new or old databases are fine.
>> For a soft upgrade I think there is a problem if the db generates enough
>> log files to start using the new bits, and then the software is reverted
>> to before the fix.
>>
>> Seems like using the bits needs to be somehow only enabled for hard
>> upgrade.  It would be best if it was controlled just by hard upgrade,
>> but if that is not possible then just doing it for databases created
>> since this version would also work - but still leave problems with old
>> hard upgraded databases.
>>
>> I have reviewed the code and am running tests.  I plan on committing
>> this part of the fix and let you address upgrade issues with a follow on
>> patch.
>>
>> Suresh Thalamati wrote:
>>



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