On 2023-08-11 00:58, Jonathan S. Katz wrote:
> [please keep replies on the mailing list]
Also noticed something else a bit non-optimal. The info about the
post-upgrade BRIN indexing steps is different between the online
Release Notes vs what was sent out in the email.
Email:
If you use
[BRIN]((https://www.postgresql.org/docs/current/brin-intro.html))
indexes to look up `NULL` values, you will need to
[reindex](https://www.postgresql.org/docs/current/sql-reindex.html)
them after upgrading to this release. On PostgreSQL 12 and above, you
can use
[`REINDEX
CONCURRENTLY`](https://www.postgresql.org/docs/current/sql-reindex.html)
to avoid blocking writes to the affected index and table, for example:
```
REINDEX INDEX CONCURRENTLY your_index_name;
```
Release notes:
Fix confusion between empty (no rows) ranges and all-NULL ranges in
BRIN indexes,
as well as incorrect merging of all-NULL summaries (Tomas Vondra)
Each of these oversights could result in forgetting that a BRIN index
range
contains any NULL values, potentially allowing subsequent queries that
should
return NULL values to miss doing so.
This fix will not in itself correct faulty BRIN entries. It's
recommended to
REINDEX any BRIN indexes that may be used to search for nulls.
The email has extra, helping info for people doing the upgrade. That
should
probably be added to the web accessible release notes as well. :)
Regards and best wishes,
Justin Clift