http://digikam.185.s1.nabble.com/Physical-Photos-and-film-inventory-management-tp4705309p4705326.html
Hi,
If i try to resume, you have a separated 'database' to merge somewhere in digiKam database table to achieve the inventory.
I don't recommend to touch directly the DK database table directly, but to patch files metadata (or sidecar) with new XMP metadata which will be imported in database automatically. The XMP as plenty of tags dedicated for your use case, and digiKam is able to backport these tags a new properties in database.
Look in setup/template. All these field are saved in database while file scanning, and each one as an XMP entry.
In you want to know the XMP tags relevant of each entry, go to Item/Edit metadata/XMP and adjust a vulue somewhere and save. Now look where in XMP the data have been patched with Exiftool or Exiv2 CLI tool.
Now to automatize the xmp values in files (or sidecar), you will need to write a script to extract each fields from CSV and write value in XMP. Again here, exiftool and exiv2 can help.
Best
Gilles Caulier