Bruce Momjian <bruce@momjian.us> writes:
> Not sure about backpatching. default_transaction_read_only has been
> around since 7.4. Setting it to true would cause pg_dump to fail unless
> you changed the database setting, and pg_dumpall would fail completely
> as there is no way to turn off the database setting.
No, neither pg_dump nor pg_dumpall would fail. What would fail is
restoring into a database that has this option already set. It's possible
that users of this option haven't noticed it because they never attempted
a restore in such a context.
> The problem is that I don't remember any report of this failing in
> pg_dump, pg_dumpall, or pg_upgrade, so saying it is a major issue is
> hard to accept.
Yeah, it's a minor issue at best, but perhaps worth fixing since
the solution is so easy.
The bigger picture here is that there are lots of ways to break
pg_upgrade via not-sane settings, and there always will be.
I don't think we should try to promise that there won't be.
regards, tom lane