[Digikam-users] Best method to move the complete photo collection

[cl at isbd.net]

Gilles Caulier <caulier.gilles at gmail.com> wrote:
> 2015-03-24 10:50 GMT+01:00  <cl at isbd.net>:
> > Gilles Caulier <caulier.gilles at gmail.com> wrote:
> >> > All very true but it's very, very risky I think.  You are always at
> >> > risk of losing the metadata.
> >> >
> >> > As far as I understand how things work if your main digikam store
> >> > fails in any way you will lose the metadata if it's stored only in the
> >> > database.  This is because Digikam will reconstruct the database when
> >> > you restore from backup.  Backing up the database file doesn't help
> >> > because it won't work on a new disk drive, Digikam rebuilds it. (Well
> >> > it might work if you restore to exactly the same place on the same
> >> > disk drive but that assumes the disk drive hasn't failed)
> >> >
> >> > There needs to be a way to copy a collection of Digikam images and its
> >> > database in a way that allows copying the metadata from one database
> >> > file to another.  At present I think the only way to copy is to write
> >> > all the metadata to file, then copy all the image files, then recreate
> >> > the database from the metadata in the files.
> >> >
> >>
> >> Not at all..
> >>
> >> digiKam identify collection from disk using UUID. This ID is stored in DB.
> >>
> > Which is why, by default, if you move a digikam hierarchy it rebuilds
> > the database.
> 
> no, not in this case.
> 
> Typical use case that i do recently : one SSD 500Go changed as SSD 1To
> to store whole collection. Both disks use Ext4.
> 
> 1/ I copied data from 500Go SSD to 1To SSD
> 2/ I removed 500Go SSD
> 3/ Mount point of 1To SSD is the same than 500Go SSD : /mnt/data
> 4/ I started digiKam
> 5/ 500Go SSD disapear and digiKam see it (through Solid interface)
> 6/ 1To SSD appears and digiKam detect it.
> 7/ quickly at startup a dialog will appear to inform user about change
> and ask to relocate DB information about missing disk to new one. A
> question is ask for each root collection setup in digiKam. In fact the
> new UUID from new disk replace old UUID in DB.
> 8/ No scan is performed. No DB rebuild. digiKam start quickly.
> 
> Operation duration : 10-30 seconds, depending of root collections
> configured in old disk.
> 
Well in my case it was simply:-

    rsync -a    /home/chris/pictures    laptop:/home/chris/pictures

and there was no way I could get the laptop to use the digikam
database file copied across, it *always* rebuilt it.

Is the database somehow referred to the mount point?  Could this could
be changed/relaxed so that it is possible to do what I want to do,
that is copy a digikam hierarchy from one computer to another easily?

-- 
Chris Green
·