Open Stack

I would like to build some stats related to openstack gerrit reviews and I would like to know few things:
* how can I get a dump of the reviews with all comments?  (queries on live DB are not an option)
* did anyone already invested time in this direction? (happy to team-up instead of having a DIY)

One graph I do want to build is would be with average number of rechecks done on reviews before they are merged, per month. As you can see that is not a trivial query to do but is doable.

Another metric it would be fun to build is the estimated failure-rate for a single CR. As I can compute an average failure rase for each job, it should not be hard to compute an estimate failure rate when I have a the list of jobs triggered for specific change. That second one may not be very practical but I am really curious what kind of values I would endup with (obvious the range would vary a lot between projects).

Thanks
Sorin