Обсуждение: BUG #16593: pg_upgrade make corrupt UK indexes

The following bug has been logged on the website:

Bug reference:      16593
Logged by:          László Tóth
Email address:      hali19790320@gmail.com
PostgreSQL version: 9.6.19
Operating system:   centos7
Description:

We upgrade from 9.6 Centos7 to 12.3 Centos 8

1. Stop 9.6
2. rsync 9.6 data and bin files from Centos7 to Centos8 (pre installed 12)
3. pg_upgrade
4. ./analyze_new_cluster.sh
5. ./delete_old_cluster.sh

We found amcheck and throwed exception!

But yes, by amcheck wiki 
https://www.postgresql.org/docs/10/amcheck.html

Whe select is a little bit missunderstandable. I think it will be a little
bit more understandable if write the function is for check one index. So the
query where statement (LIMIT 10 and AND n.nspname = 'pg_catalog' ) ignores a
lot of serious index validation! 

It will be very useful a checklist how can we be sure the upgrade is
succesful!

Thank you!

Here documented it:

https://stackoverflow.com/questions/63588123/postgres-pg-upgrade-corrupt-indexes-uk-missing-values-though-missing-records-b

On Wed, Aug 26, 2020 at 09:49:00AM +0200, Magnus Hagander wrote:
> 
> 
> On Wed, Aug 26, 2020 at 7:38 AM Nick Cleaton <nick@cleaton.net> wrote:
> 
>     On Tue, 25 Aug 2020 at 23:55, PG Bug reporting form <noreply@postgresql.org
>     > wrote:
> 
>         We upgrade from 9.6 Centos7 to 12.3 Centos 8
> 
> 
>     This from https://www.postgresql.org/docs/12/amcheck.html#id-1.11.7.11.9
>     might be relevent:
> 
>     > Comparisons of datums of a collatable type like text must be immutable
>     (just as all comparisons used for B-Tree index scans must be immutable),
>     which implies that operating system collation rules must never change.
>     Though rare, updates to operating system collation rules can cause these
>     issues. More commonly, an inconsistency in the collation order between a
>     master server and a standby server is implicated, possibly because the 
>     major operating system version in use is inconsistent
> 
> 
> And in particular also see https://wiki.postgresql.org/wiki/Locale_data_changes
> , which shows that the step from Centos7 to Centos8 is one that causes this
> problem. You need to reindex all text/varchar indexes when you  make that
> upgrade.

And we should have a script ready for people to do this.  :-)

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

  The usefulness of a cup is in its emptiness, Bruce Lee