We have discussed tag propagation before.
I thought I understood the logic, but it seems as if you have changed it.
For example: since it isn’t possible to focus on albums based on artist nationality (@Danny has talked about this coming), I do a trick using tags. In the artist browser I periodically focus on artists based on nationality, and tag them Jazz Nordic and Jazz Italian. (Yes, this means Verdi gets tagged as a jazz artist, I have to do some cleanup.) Now I can focus on these tags in the album browser — tags propagate, even though nationality attributes do not.
But here is the strange new behavior:
In the Artist browser, I focus on Jazz Nordic. Abdullah Ibrahim shows up, even though he is South African. But when I open him, he doesn’t have that tag.
Since the tag filtering mostly seems to work, I wondered if there was an album tagged as Jazz Nordic due to another contributor and that tag reverse-propagated. I didn’t find one, but there may be a hidden contributor or composer, the jazz world is globalized. I can research more, but the question is: does the tag reverse-propagate like that, from album to artist? I don’t think I have seen that before. I may be wrong. But have you changed this query behavior?
EDIT One reason I thought it may be reverse propagation is that a Bill Evans showed up under Nordic, and he did an album with Monica Zetterlund who is Nordic.
It’s not a critical problem, invalidates my workaround, but we know there will be a better solution…
EDIT Ah, I found it. There is an album under Ibrahim that is tagged Jazz Nordic, presumably because the NDR Big Band has a Swedish-born member. So that indicates there is reverse propagation.
Cool, but it can lead to weird results, as people play with other people — attributes may propagate across the entire database.
Probably also the reason these filters are really, really slow, including changing the sort order (so it resorts the query, not the previous query result).