Re: exposing pg_controldata and pg_config as functions

On Mon, Jan 18, 2016 at 07:50:12PM -0500, Bruce Momjian wrote:
> > >>>> 1) Change NextXID output format from "%u/%u" to "%u:%u"
> > >>>>    (see recent hackers thread)
> > >>>
> > >>> !     printf(_("Latest checkpoint's NextXID:          %u/%u\n"),
> > >>>              ControlFile.checkPointCopy.nextXidEpoch,
> > >>>              ControlFile.checkPointCopy.nextXid);
> > >>>       printf(_("Latest checkpoint's NextOID:          %u\n"),
> > >>> --- 646,652 ----
> > >>>              ControlFile.checkPointCopy.ThisTimeLineID);
> > >>>       printf(_("Latest checkpoint's full_page_writes: %s\n"),
> > >>>              ControlFile.checkPointCopy.fullPageWrites ? _("on") : _("off"));
> > >>> !     printf(_("Latest checkpoint's NextXID:          %u:%u\n"),
> > >>> This should be definitely a separate patch.
> > >>
> > >> Ok. Notwithstanding Simon's reply, there seems to be consensus that this
> > >> is the way to go. Will commit it this way unless some additional
> > >> objections surface in the next day or so.
> > >
> > > FYI, this slash-colon change will break pg_upgrade unless it is patched.
> > > Dp you want a patch from me?
> >
> > Didn't realize that -- yes please.
>
> Sure, attached, and it would be applied only to head, where you change
> pg_controldata.  pg_upgrade has to read the old and new cluster's
> pg_controldata.  We could get more sophisticated by checking the catalog
> version number where the format was changed, but that doesn't seem worth
> it, and is overly complex because we get the catalog version number from
> pg_controldata, so you would be adding a dependency in ordering of the
> pg_controldata entries.

Sorry, please use the attached patch instead, now tested with your
changes.

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

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