I'd like to create mixes based on my own catalog and some remote service. To achieve this I use multiple bucket values, eg.:
http://developer.echonest.com/api/v4/playlist/dynamic/create?bucket=id%3Arhapsody-US&bucket=tracks&bucket=id%3ACAxxxxxxxx&artist=King%20Crimson&artist=Yes&type=artist-radio
When using rhapsody, I would get many songs back which come without any ID, neither from my catalog nor from rhapsody. Using Deezer I would get either or, or even both. That's a bit odd, as using rhapsody alone seems to not return those songs without a rhapsody ID.
I tried to use the "limit" parameter. Its description says "if 'true', limit the results to any of the given idspaces or catalogs". Does this mean the API would pick just one of my list, and use this one exclusively? That's what I'm seeing. But I would have expected the mix to then only return songs which are in at least one of my id spaces. Is this wrong?