Re: preserving db/ts/relfilenode OIDs across pg_upgrade (was Re: storing an explicit nonce)

On Sat, Jan 22, 2022 at 12:47:35PM +0530, Shruthi Gowda wrote:
> On Sat, Jan 22, 2022 at 12:27 AM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> >
> > Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> > > It seems to me that what this comment is saying is that OIDs in the
> > > second and third categories are doled out by counters. Therefore, we
> > > can't know which of those OIDs will get used, or how many of them will
> > > get used, or which objects will get which OIDs. Therefore, I think we
> > > should go back to the approach that you were using for template0 and
> > > handle both that database and postgres using that method. That is,
> > > assign an OID manually, and make sure unused_oids knows that it should
> > > be counted as already used.
> >
> > Indeed. If you're going to manually assign OIDs to these databases,
> > do it honestly, and put them into the range intended for that purpose.
> > Trying to take short-cuts is just going to cause trouble down the road.
>
> Understood. I will rework the patch accordingly. Thanks

Thanks. To get the rsync update reduction we need to preserve database
oids.

--
Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EDB https://enterprisedb.com

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