How to prevent a desktopcouch DB from syncing to UbuntuOne

I just had a Skype call with Stuart Langridge where he kindly answered a bunch of questions I had about desktopcouch and UbuntuOne.

I learned two important things:

1. If you're paired with UbuntuOne, all desktopcouch databases will by default be bi-directionally synced with UbuntuOne
2. There's a way to prevent specific databases from syncing

I've been working on dmedia lately and frequently delete its CouchDB database and re-run an import of all my media files.  I noticed that strangle old documents present in a previously deleted database would show up again, which made me suspect that they were getting synced back from UbuntuOne (which Stuart confirmed). And he shared a currently undocumented way of preventing specific databases from being synced.  Here's how:

First, open a terminal and point Firefox at Futon:

firefox .local/share/desktop-couch/couchdb.html

Then click on the management database. If you're paired with UbuntuOne, you'll have a document with a "service_name" of "ubuntuone", and a "record_type" of "http://www.freedesktop.org/wiki/Specifications/desktopcouch/paired_server". All you need to do is add an "excluded_names" attribute with a list of database names, like this:

"excluded_names": ["dmedia", "dmedia_test"]

Thanks, Stuart!