Re: pgsql: Trial fix for old cross-version upgrades.

On Fri, 2025-02-21 at 21:57 -0500, Tom Lane wrote:
> Hmm.  I forced my local BF installation to run a v17-to-HEAD upgrade
> test, and it still failed, though seemingly with fewer diffs than
> the buildfarm is reporting for older branches.  (Diffs attached for
> amusement's sake.)  I don't believe we've made any definitional
> changes in the contents of pg_statistic since v17, so whatever's
> going on here seems a little subtler than I was hoping.

Also the non-buildfarm tests (src/bin/pg_upgrade/TESTING) are all
passing for versions 10+.

> I wonder if it'd be a good idea to rearrange TestUpgradeXversion.pm
> so that instead of testing upgrades from oldest prior version to
> newest, it tested from newest to oldest?  My thought here is that
> the oldest cases are most likely to fail, and when they do, it'd
> be valuable information to know which branches still work.

That's a good idea and would be a big help.

Regards,
    Jeff Davis