I dont know the history of composer changing, but I would think this happens very rarely ?

I didn't think composer had changed at all... I was told I should never change the name of the relationship, for this exact reason.

http://chatlogs.musicbrainz.org/musicbrainz-devel/2011/2011-12/2011-12-05.html

Seems trivial, but lets agree on the attribute name as this can always cause arguments

Don't ask me, I'm very bad for naming stuff

Here is a real case: http://lists.musicbrainz.org/pipermail/musicbrainz-style/2012-March/015054.html

Moving to 3mo as per due date

We use 'id' for UUIDs elsewhere. Since this isn't an ID for the tag it's on, but rather for the type, I think type-id is perfectly fine. I'd suggest removing the '' except we've already specified we don't care about making things harder for people using languages that prefer a dot notation and see '' as an operator, so we should keep it for clarity in terms of separating the "namespace" (type) from the "element" (id) (roughly).

Likewise in the JSON. Just stick a "type-id" alongside wherever we currently put "type".

We decided that type-id was fine in the dev meeting. This can proceed.

https://github.com/metabrainz/musicbrainz-server/pull/65