I was running a quite old version (13) on my webspace and without prewarning the provider upgraded PHP to 7.4 and now Nextcloud refused to work any longer.
I also did not find a way to upgrade the existing installation and I had to do a fresh installation.
Current Version is 20.
Now I need to get my addressbook back from the old installation.
I could not see any addressbook related files in /data/MyAccount and thind, the contacts are stored in the old MySQL db.
Is there a way to export the contacts from the old db and import them to the database of the new installation?