Re: pg_upgrade 9.6->9.6: column "amtype" does not exist

On Fri, Apr  1, 2016 at 05:55:58PM -0400, Tom Lane wrote:
> Alvaro Herrera <alvherre@2ndquadrant.com> writes:
> > The reason for the failure is that pg_dump knows that 9.6 installations
> > have the amtype column -- but on your older devel 9.6 install, it
> > doesn't exist.  To fix it we would have to compare catalog versions in
> > pg_dump rather than major version, but we don't that anywhere.  Anyway
> > many upgrades could fail depending on other patches because of the same
> > reason.  I don't think we need to fix this.
> 
> We've never expected pg_dump to be able to handle intermediate development
> versions.  It's enough of a maintenance burden that it knows how to dump
> from all previous stable branches.

Pg_upgrade does handle catalog version changes.  I don't think we ever
anticipated catalog changes that would throw errors in pg_dump, which
pg_upgrade relies on.  I am saying that someday we might need pg_dump to
track catalog versions.  However, I am not even sure how pg_dump would
check the catalog version.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com

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