Stats Disappear After Minor Upgrade?

Me again.

I'm testing an upgrade of a database from 9.2.10 to 9.2.22. The upgrade
seemingly had no problems and I started the DB. However when I went to look
at some vacuum-related status, every table had n_dead_tup and n_live_tup =
0.

For what it's worth, this DB was a clone of a prod standby. I didn't think
to check the stats after opening the new clone (renamed the recovery.conf),
so I can't say for sure what it looked like prior to upgrade. I've kicked
off a DB-wide analyze but obviously that takes a long time and more or less
would mean prod app downtime as the optimizer would make all sorts of goofy
decisions until the stats are in place.

I just wanted to ask here if anything like this is known. I know 10->22 is
a bit of a leap but it's still the same major branch so I didn't expect any
trouble. My other tests in small sandboxes were from 9.2.18 or .21 to
9.2.22 and had no problems like this.

Don.

--
Don Seiler
www.seiler.us