Bug 264745

Version:           1.9.0 (using KDE 4.4.5) 
OS:                Linux

When adding a new tag to multiple images (haven't checked for just one image), all tags not shared by the selected images are removed from all selected images. These tags are still in the database and can be restored by synching databases and images. Per http://digikam.1695700.n4.nabble.com/digiKam-ate-my-tags-bug-feature-or-user-error-td3238857.html, this bug seems to have been around for a while. It is also in the digiKam 2 beta.



Reproducible: Always

Steps to Reproduce:
 Select a bunch of images and add a new tag. Open the metadata xmp sidebar and note that all tags not in common to all the selected images are gone. Look at the images thumbs and if you have digiKam configured to show tags, you'll see that the tags are still in the database.



Actual Results:  
When the new tag is written to the image metadata of multiple selected images, all the tags not in common to all images are removed from the metadata, though not from the database.

Expected Results:  
When writing a new tag to metadata of multiple images, the old tags should remain in the metadata as well as in the database. The new tags should be added to the old tags, rather than replace the old tags.

If you are unfortunate enough to assume that having digiKam configured to write metadata to your images is sufficient protection to get tags into images' metadata, and you discard your old database and make a new one, then you just lost all your tags. I lost "who" and "where" tags for 1100 images this way. Fortunately, I had a backup of all the images and so was able to retrieve my lost tags. 

The work-around is to end all tagging sessions with"Tools, 'write metadata to all images'" to restore the removed metadata. Which raises the question of why have digiKam write metadata while tagging, if it needs to be redone at the end of the tagging session.