On Wed, Jul 27, 2016 at 12:47 PM, Bruce Momjian <bruce@momjian.us> wrote:
> Yes. I was saying I don't know how to improve pg_upgrade to address it.
This problem is there even in oracle/db2/sqlserver. None of them allow
rollback to the lower version
unless it is a minor version upgrade. Major version upgrade almost
definitely involves change in transaction log
(WAL) structure and hence no rollback.