Comment 0 for bug 781600

For the Ensemble work we've been debating, we need a way to list (location, tip revision id) for all branches of a distribution (principia, in our case).

Since this list will hopefully get huge over time, we'll also need a way to ask for the changes since a given date, in which case we'd only get (location, tip revision id) for those branches that are either new or have had changes to their tip revision id since the provided timestamp.

Please note that we don't need/want *all the data* for a branch in that list, since it's going to be quite a lot of unnecessary information being transferred over the wire.

For reference only, in a conversation with Jono over UDS, he's come up with this sketched query which would do something resembling what we'd need:

SELECT unique_name, last_scanned_id FROM Branch JOIN DistroSeries ON
Branch.distroseries = DistroSeries.id JOIN Distribution ON
DistroSeries.distribution = Distribution.id WHERE Distribution.name =
'ubuntu' AND branch.last_scanned > '2011-05-01';