Testing multiple databases

Does anyone have any experience testing multiple databases? I’m working
on an
application that relies on an external data feed, which gets updated
every
night. My models consist of the models in my app database, and a bunch
of
models all subclassed from CAPBase, which connects to the data feed.

However… part of the functionality of the application depends on
monitoring
the changes in the data feed (eg when items are added or deleted, or
when
prices change). How can I use fixtures to achieve this? I’m sure I’ve
seen
something about it online but I can’t find anything in the multiple
database
page on the wiki.

Thanks

Ashley