What’s supposed to happen, if you click on the small box tagged “primary” in the window, where you add aliases? I tried. Nothing visible happened to the order of the aliases.
I just tested it and you are right, it doesn’t seem to have a function. Looks pretty though!
That is a mystery to me too.
I wasn’t part of the project when the schema was designed, and I’ve wondered what the potential uses for it would be.
Theoretically, it allows you to define what is the canonical name (and script) in each language. That being said, it isn’t currently used for anything, as you’ve found out.
It will eventually be used to sort aliases.
I would have thought the primary is the original language title of the Work. I can’t see the point in sorting the order of the aliases. Maybe someone can suggest other uses for this function.
Personally I also wonder about the “primary” checkbox on aliases. i even wanted to create a ticket for this! as it is right now, I kinda don’t see the point :/
“Primary” has no impact on the web UI (maybe they are somehow sorted more to the top of the alias list, but I’m not sure about this).
The real impact is just in Picard, when the option “Metadata” – “Translate artist names to this locale where possible” (for the selected language) is activated.
If you see e.g.
If you have activated the translation you will get e.g.
“Pyotr Ilyich Tchaikovsky” as English translation or
“Pjotr Iljitsch Tschaikowski” as German translation.
See http://picard-docs.musicbrainz.org/en/config/options_metadata.html (even if it doesn’t mention that just the primary alias is used).
Pls. note, that IMHO this only affects artist names as release artist or track artist, but not for other tags, e.g. composer.