Deleting empty music genres

[PaulMc]

I've a large music collection on a NAS and have recently had time to clean up the metadata on the audio files. This has resulted in a few genres becoming empty (mainly because of typos). However, I cannot find a way of removing them permanently. I've used the trick of renaming them, which then works for a short while but then the next morning they are all back. I've manually rescanned the library folder replacing all metadata (but not images), and this makes no difference - they return the next day. I presume the reappearance is because of a setting in the overnight scheduled processes? I've double checked the metadata using other software and cannot see these phantom genres anywhere however they keep returning and are empty when selected in the Jellyfin UI. Please can anyone suggest a process by which I can remove these genres permanently?

[mellowmint]

I had a situation where I inadvertently dropped 1 album of song files into an artist's folder directly, like I didn't make an album folder.
Well, no album folder means no album displayed in Jellyfin, which means those songs weren't shown under the artist either.

The only place these songs had presence in Jellyfin was under the "Songs" section, a single file list which basically made them invisible.
~250 artists, ~1000 albums, ~11,000 songs, and 9 of those songs aren't represented on any artist or album page, just somewhere in a 11,000 item list
Easy to notice, right?

A genre "alternativa e indie" was only on this one album, so I scrubbed that. But the genre keeps coming back. Except no other albums had that genre. Especially after scrubbing the one instance, it really felt like I fixed the source of the genre occurring but Jellyfin wasn't updating or Jellyfin was holding onto old data or something. I was wrong.

If you are deleting it and it's recreating it... I bet you still have the tag somewhere.

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1. Stop Jellyfin so you can touch the database

systemctl stop jellyfin

2. Use sqlite3 to open the database

sqlite3 /var/lib/jellyfin/data/jellyfin.db

3. Genres are stored in "ItemValues" and this command will print all existing genres

SELECT DISTINCT Value FROM ItemValues WHERE Type = 2;

4. This command returns genres, if no database item is attached. But it should return empty.

SELECT DISTINCT iv.Value
FROM ItemValues iv
LEFT JOIN ItemValuesMap ivm ON iv.ItemValueId = ivm.ItemValueId
WHERE iv.Type = 2 AND ivm.ItemValueId IS NULL;

5. Replace the word Genre in the command below with any existing genre you believe should be empty / should no longer exist.
You can reference the table from step 3 if needed. This command returns all items with the named genre.

SELECT bi.Name, iv.Value
FROM BaseItems bi
JOIN ItemValuesMap ivm ON bi.Id = ivm.ItemId
JOIN ItemValues iv ON ivm.ItemValueId = iv.ItemValueId
WHERE iv.Type = 2 AND iv.Value = 'Genre';


It is a good tool to find which music files you may need to change.
I would refrain from editing the DB and only use it for investigation.
Make changes to your music files and let the DB update itself.

To exit sqlite3 again, use .quit
And don't forget to systemctl start jellyfin