On Tue, Apr 8, 2025 at 6:37 PM Tom Lane <t...@sss.pgh.pa.us> wrote: > > Hannu Krosing <han...@google.com> writes: > > I think we do preserve role oids > > Oh ... I'd been looking for mentions of "role" in > pg_upgrade_support.c, but what I should have looked for was > "pg_authid". So yeah, we do preserve role OIDs, and maybe that's > enough to make this workable, at least with source versions that > share the same rules for what goes into pg_largeobject_metadata and > pg_shdepend. It's not something I'd risk back-patching though.
The risk is why I suggest to have this in backports as something last resort which is gated on an environment variable I have been forced to do this half-manually a few times to make pg_upgrade feasible at all. Current really UGH workaround is to use pg_repack support for swapping relfilenodes of pg_largeobject_metadata with a user table before and after the upgrade and then manually patching up leftovers like pg_shdepend after pg_upgrade. These have fortunately been cases where there were no other dependencies like comments or security labels on LOs, but these to should be doable; > regards, tom lane
