Is it possible to segregate the PITR data by database at any stage? We are
i don't think so.
My guess is that at snapshot time, I could use oid2name to focus on the database I'm interested in plus core Pg data structures,
can you eleborate on this , how do you plan to use oid2name exactly?
Background: The goal here is to have a "web application rewind" facility, based on PITR, that allows a webapp administrator to say "please rewind my Moodle/Drupal/Whatever" to arbitrary point in time X, where X is in the last Y days, via a web UI. It is normally configured to rewind not the master, but a secondary install of your web app -- although there's some interest in rewinding the master too for training and software testing purposes.
not sure if the postgres PITR is designed for this kind of facility like that, i would think you will have to incorporate such facility into your application/ database design