Hi Andre,

Andre Reitz wrote:
> 
> We are trying to find a Workaround for the Bug in Version 7.4.3.32.
> 
> The well known bug is:
> - Autosave is always disabled after reboot of the Computer
> 
> Our Workaround is:
> - Set Logmode=Overwrite
> - No Logbackups

Which platform? 
Win32 ? -> it's not a bug, it's simply not possible with starting the
kernel service in Windows automatically.
Start the kernel manualy and then the dbmsrv.exe has the possibilty to
switch the AUTOLOG on. Then he is involved in the start up.

Work around on Unix: attach the command in the startup script of MaxDB: 
   dbmcli -U <Xuser-key for dbm> autolog_on <medium, if you don't have a
autolog medium>
 
> QUESTIONS:
> 
> Is the following correct?
> 
> - All changes to the Database are immediately written to the Logvolume

Yes, as soon as the transaction is commited all the log info for this
transaction is written synchronously to the log volume.

> - The same changes are perhaps in the datacache, and they are written
>   later to the Datavolume

At the next SAVEPOINT

> - If the server craches (powerfailure), and there were changes in the 
> datacache,
>   the database recounstructs the missing data from the logvolume
>   AUTOMATICALLY when warming up again.  (<- Is this really correct?)

Definitely right as long as the log is intact and wasn't touched !!!!!

> But what will happen in the same scenario when changes are
> not in the Datavolume, but only in the cache, and the Logvolume
> was cleared because it was full 1 second before the powerfailure?

Here the operator loose the right to use this name !!!

Don't ever try to use a database productively and clear log volumes or
switch it to "Auto Overwrite" or best: delete log volumes etc. 

Better don't think about this, simply do your data and log backups
regularely in the official way and be good.

> Or in other words:
> - Is it guaranteed, that in Logmode: Overwrite all changes are written
>   to the Datavolume, before the Logvolume ist cleared, when its full?

Never,  you play with your log continuation :-). Better don't try this
in productive environment.

Ralf 

__________________________________________________________________
Dr. Ralf Czekalla                         mailto:[EMAIL PROTECTED]

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