PostgreSQL 11 Beta 2 Released!

The PostgreSQL Global Development Group announces that the second beta release
of PostgreSQL 11 is now available for download. This release contains previews
of all features that will be available in the final release of PostgreSQL 11
(though some details of the release could change before then) as well as bug
fixes that were reported during the first beta.

In the spirit of the open source PostgreSQL community, we strongly encourage you
to test the new features of PostgreSQL 11 in your database systems to help us
eliminate any bugs or other issues that may exist. While we do not advise for
you to run PostgreSQL 11 Beta 2 in your production environments, we encourage
you to find ways to run your typical application workloads against this beta
release.

Upgrading to PostgreSQL 11 Beta 2
---------------------------------

To upgrade to PostgreSQL 11 Beta 2 from Beta 1 or an earlier version of
PostgreSQL, you will to use a strategy similar to upgrading between major
versions of PostgreSQL (e.g. `pg_upgrade` or `pg_dump` / `pg_restore`). For more
information, please visit the documentation section on upgrading.

Changes to Major Features of PostgreSQL 11
------------------------------------------

The PostgreSQL 11 Beta 1 release announced "Channel Binding for SCRAM
Authentication" as a major feature as it could prevent man-in-the-middle attacks
when using SCRAM authentication. During the course of testing, it was determined
that libpq, the client connection library for PostgreSQL, is unable force the
use of channel binding.

While this functionality can be fixed in a future version of PostgreSQL, for now
channel binding for SCRAM authentication will not be considered a major feature
for PostgreSQL 11.

Changes Since Beta 2
--------------------

There have been many bug fixes for PostgreSQL 11 reported during the Beta 1
period and applied to the Beta 2 release. Several bug fixes reported for version
10 or earlier that also affected version 11 are included in the Beta 2 release.
These fixes include:

* Several fixes for XML support, including using the document node as the context
for XPath queries as defined in the SQL standard, which affects the `xpath` and
`xpath_exists` functions, as well as XMLTABLE
* Several fixes related to VACUUM, including potential data corruption issues
* Fixes for partitioning, including ensuring partitioning works with temporary
tables, eliminating a needless additional partition constraint checks on
`INSERT`s and generating incorrect paths for partitionwise aggregates
* Fix for potential replica server crashes where a replica would attempt to read
a recycled WAL segment
* Fixes for `pg_replication_slot_advance` including returning `NULL` if slot is
not advanced and changes for how the slot is updated depending on if it is a
physical or logical replication slot
* Ensure `pg_resetwal` works with relative paths to data directory
* Fixes for query parallelism, including preventing a crash by ignoring
"parallel append" for parallel unsafe paths in a query plan
* Fix returning accurate results with `variance` and similar aggregate functions
when executed using parallel query
* Fix issue where `COPY FROM .. WITH HEADER` would drop a line after every
4,294,967,296 lines processed
* Ensure the "B" (bytes) parameter is accepted by all memory-related
configuration parameters
* Several fixes for the JSONB transform in PL/Python and PL/Perl
* Fix for plpgsql checking statements where it needs to check original write
statement before rewrite, could cause crash
* Fix for `SHOW ALL` to display superuser configuration settings to roles that
are allowed to read all settings
* Fix for `pg_upgrade` that ensures defaults are written when using the "fast
ALTER TABLE .. ADD COLUMN" feature with a non-NULL default
* Several fixes for memory leaks
* Several fixes specific to the Windows platform

This update also contains tzdata release 2018e, with updates for North Korea.
The 2018e also reintroduces the negative-DST changes that were originally
introduced in 2018a, which affects historical and present timestamps for Ireland
(1971-), as well as historical timestamps for Namibia (1994-2017) and the former
Czechoslovakia (1946-1947). If your application is storing timestamps with those
timezones in the affected date ranges, we ask that you please test to ensure
your applications behave as expected.

Testing for Bugs & Compatibility
--------------------------------

The stability of each PostgreSQL release greatly depends on you, the community,
to test the upcoming version with your workloads and testing tools in order to
find bugs and regressions before the release of PostgreSQL 11. As this is a
Beta, minor changes to database behaviors, feature details, and APIs are still
possible. Your feedback and testing will help determine the final tweaks on the
new features, so please test in the near future. The quality of user testing
helps determine when we can make a final release.

A list of open issues is publicly available in the PostgreSQL wiki. You can
report bugs using this form on the PostgreSQL website:

https://www.postgresql.org/account/submitbug/

Beta Schedule
-------------

This is the second beta release of version 11. The PostgreSQL Project will
release additional betas as required for testing, followed by one or more
release candidates, until the final release in late 2018. For further
information please see the Beta Testing page.

Links
-----

* Download: https://www.postgresql.org/download/
* Upgrading: https://www.postgresql.org/docs/11/static/upgrading.html
* Beta Testing Information: https://www.postgresql.org/developer/beta/
* PostgreSQL 11 Beta Release Notes: https://www.postgresql.org/docs/11/static/release-11.html
* PostgreSQL 11 Open Issues: https://wiki.postgresql.org/wiki/PostgreSQL_11_Open_Items
* Submit a Bug: https://www.postgresql.org/account/submitbug/