[Digikam-users] How to Sync Albums Across Machines?

[Jean-François Rabasse]

On Wed, 20 Feb 2013, Mick Sulley wrote:

> Hi,
>
> When I sync my album between laptop and desktop I get a message when I open 
> it on the destination machine saying that the collection is available but the 
> identifier has changed.
>
> I have looked in the database on each machine and it seems that the problem 
> is that the AlbumRoots table is slightly different, the identifier field is 
> different -
> desktop = "volumeid:?uuid=bf835257-ad63-4580-9692-9d2600740cd1"
> laptop = "volumeid:?uuid=2a6a238c-c404-46b6-886f-873683917b9c"
>
> It does seem to be OK if I just accept the message and continue, but is there 
> any way to stop it happening?  Is it likely to cause any problems?

Hi Mick,

Well, this is an old issue, often discussed on this list.
Identifying disk devices by UUID, instead of mount pathname as it should
be - at least on Unix platforms - makes the database hardware dependant.

Same problem occurs if you manage your collections on USB drives, even on
the same machine. Changing a drive by a backup drive, or replacing an old
drive by a new one with a mirror copy of collections will also change the
physical device UUID.

The (dirty) fix to work around sync problems is to use small scripts to
make the transfert, e.g. using rsync, then update the database from
SQL command line tool and issue things like that :
UPDATE albumroots SET identifier = 'volumeid:?uuid= new UUID'
  WHERE identifier = 'volumeid:?uuid = old UUID';

Jean-François