Re: the big picture for index-only scans

Robert Haas wrote:
> > I am happy to have pg_upgrade skip upgrading visibility map files --- it
> > already has code to conditionally process them because they only exist
> > in >= 8.4:
> >
> > ? ? ? ?/* fsm/vm files added in PG 8.4 */
> > ? ? ? ?if (GET_MAJOR_VERSION(old_cluster.major_version) >= 804)
> > ? ? ? ?{
> > ? ? ? ? ? ?/*
> > ? ? ? ? ? ? * Copy/link any fsm and vm files, if they exist
> > ? ? ? ? ? ? */
> >
> > Just give the word and it will be done.
> 
> I hereby give the word.  :-)
> 
> Specifically, we need to skip copying vm files (only) if coming from a
> version prior to this commit:
> 
> http://git.postgresql.org/gitweb/?p=postgresql.git;a=commit;h=e16954f3d27fa8e16c379ff6623ae18d6250a39c

Done with the attached, applied patch.  There was no cat-version bump
from that commit (because the format didn't change, just the
crash-safeness) so I picked the first cat-version change after this
commit.  This is only a pg_upgrade 9.2+ issue.

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

  + It's impossible for everything to be true. +