[DaveBlake]

I did something like
delete from artist where idArtist between 1894 and 1920

All of these artists were added at the smae time so the Artist IDs were sequential. Is that what you would have done?

No.  I would not have just deleted artists willy nillly. I would have first checked that there actually were orphaned or duplicate artists. Then if there were I would have investigated further why the clean process was not removing them, and see if I could deduce more about what had happened.  I suspect that it is not just about some unwanted artists, but I can learn nothing from this, it is a dead end. Kodi can not be improved, nor other users benefit.

Yes SQL syntax is very obvious, yet SQL is very also powerful. Your data is yours to do with as you wish, but I caution all users that manually meddling is not something to undertake unless you know what you are doing, and have some understanding of the entire data model. It is easy to make things worse not better.

You seem happy with the outcome, but should you have further problems then please remind others that you have manually deleted artists from your music db.