Waiting for PostgreSQL 17 – Add new COPY option SAVE_ERROR_TO / Rename COPY option from SAVE_ERROR_TO to ON_ERROR

On 16th of January 2024, Alexander Korotkov committed patch:

Add new COPY option SAVE_ERROR_TO
 
Currently, when source data contains unexpected data regarding data type or
range, the entire COPY fails. However, in some cases, such data can be ignored
and just copying normal data is preferable.
 
This commit adds a new option SAVE_ERROR_TO, which specifies where to save the
error information. When this option is specified, COPY skips soft errors and
continues copying.
 
Currently, SAVE_ERROR_TO only supports "none". This indicates error information
is not saved and COPY just skips the unexpected data and continues running.
 
Later works are expected to add more choices, such as 'log' and 'table'.
 
Author: Damir Belyalov, Atsushi Torikoshi, Alex Shulgin, Jian He
Discussion: https://postgr.es/m/87k31ftoe0.fsf_-_%40commandprompt.com
Reviewed-by: Pavel Stehule, Andres Freund, Tom Lane, Daniel Gustafsson,
Reviewed-by: Alena Rybakina, Andy Fan, Andrei Lepikhov, Masahiko Sawada
Reviewed-by: Vignesh C, Atsushi Torikoshi

and then, three days later, he changed the syntax in next patch:

Rename COPY option from SAVE_ERROR_TO to ON_ERROR
 
The option names now are "stop" (default) and "ignore".  The future options
could be "file 'filename.log'" and "table 'tablename'".
 
Discussion: https://postgr.es/m/20240117.164859.2242646601795501168.horikyota.ntt%40gmail.com
Author: Jian He
Reviewed-by: Atsushi Torikoshi

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Waiting for PostgreSQL 17 – Support identity columns in partitioned tables

On 16th of January 2024, Peter Eisentraut committed patch:

Support identity columns in partitioned tables
 
Previously, identity columns were disallowed on partitioned tables.
(The reason was mainly that no one had gotten around to working
through all the details to make it work.)  This makes it work now.
 
Some details on the behavior:
 
* A newly created partition inherits identity property
 
  The partitions of a partitioned table are integral part of the
  partitioned table.  A partition inherits identity columns from the
  partitioned table.  An identity column of a partition shares the
  identity space with the corresponding column of the partitioned
  table.  In other words, the same identity column across all
  partitions of a partitioned table share the same identity space.
  This is effected by sharing the same underlying sequence.
 
  When INSERTing directly into a partition, the sequence associated
  with the topmost partitioned table is used to calculate the value of
  the corresponding identity column.
 
  In regular inheritance, identity columns and their properties in a
  child table are independent of those in its parent tables.  A child
  table does not inherit identity columns or their properties
  automatically from the parent.  (This is unchanged.)
 
* Attached partition inherits identity column
 
  A table being attached as a partition inherits the identity property
  from the partitioned table.  This should be fine since we expect
  that the partition table's column has the same type as the
  partitioned table's corresponding column.  If the table being
  attached is a partitioned table, the identity properties are
  propagated down its partition hierarchy.
 
  An identity column in the partitioned table is also marked as NOT
  NULL.  The corresponding column in the partition needs to be marked
  as NOT NULL for the attach to succeed.
 
* Drop identity property when detaching partition
 
  A partition's identity column shares the identity space
  (i.e. underlying sequence) as the corresponding column of the
  partitioned table.  If a partition is detached it can longer share
  the identity space as before.  Hence the identity columns of the
  partition being detached loose their identity property.
 
  When identity of a column of a regular table is dropped it retains
  the NOT NULL constraint that came with the identity property.
  Similarly the columns of the partition being detached retain the NOT
  NULL constraints that came with identity property, even though the
  identity property itself is lost.
 
  The sequence associated with the identity property is linked to the
  partitioned table (and not the partition being detached).  That
  sequence is not dropped as part of detach operation.
 
* Partitions with their own identity columns are not allowed.
 
* The usual ALTER operations (add identity column, add identity
  property to existing column, alter properties of an indentity
  column, drop identity property) are supported for partitioned
  tables.  Changing a column only in a partitioned table or a
  partition is not allowed; the change needs to be applied to the
  whole partition hierarchy.
 
Author: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://www.postgresql.org/message-id/flat/CAExHW5uOykuTC+C6R1yDSp=o8Q83jr8xJdZxgPkxfZ1Ue5RRGg@mail.gmail.com

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Waiting for PostgreSQL 17 – In plpgsql, allow %TYPE and %ROWTYPE to be followed by array decoration.

On 4th of January 2024, Tom Lane committed patch:

In plpgsql, allow %TYPE and %ROWTYPE to be followed by array decoration.
 
This provides the useful ability to declare a variable that is an array
of the type of some other variable or some table column.
 
Quan Zongliang, Pavel Stehule
 
Discussion: https://postgr.es/m/ec4523e1-9e7e-f3ef-f9ce-bafd680ad6f6@yeah.net

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Waiting for PostgreSQL 17 – ALTER TABLE command to change generation expression

On 4th of January 2024, Peter Eisentraut committed patch:

ALTER TABLE command to change generation expression
 
This adds a new ALTER TABLE subcommand ALTER COLUMN ... SET EXPRESSION
that changes the generation expression of a generated column.
 
The syntax is not standard but was adapted from other SQL
implementations.
 
This command causes a table rewrite, using the usual ALTER TABLE
mechanisms.  The implementation is similar to and makes use of some of
the infrastructure of the SET DATA TYPE subcommand (for example,
rebuilding constraints and indexes afterwards).  The new command
requires a new pass in AlterTablePass, and the ADD COLUMN pass had to
be moved earlier so that combinations of ADD COLUMN and SET EXPRESSION
can work.
 
Author: Amul Sul <sulamul@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAAJ_b94yyJeGA-5M951_Lr+KfZokOp-2kXicpmEhi5FXhBeTog@mail.gmail.com

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Waiting for PostgreSQL 17 – Add support for incremental backup.

On 20th of December 2023, Robert Haas committed patch:

Add support for incremental backup.
 
To take an incremental backup, you use the new replication command
UPLOAD_MANIFEST to upload the manifest for the prior backup. This
prior backup could either be a full backup or another incremental
backup.  You then use BASE_BACKUP with the INCREMENTAL option to take
the backup.  pg_basebackup now has an --incremental=PATH_TO_MANIFEST
option to trigger this behavior.
 
An incremental backup is like a regular full backup except that
some relation files are replaced with files with names like
INCREMENTAL.${ORIGINAL_NAME}, and the backup_label file contains
additional lines identifying it as an incremental backup. The new
pg_combinebackup tool can be used to reconstruct a data directory
from a full backup and a series of incremental backups.
 
Patch by me.  Reviewed by Matthias van de Meent, Dilip Kumar, Jakub
Wartak, Peter Eisentraut, and Álvaro Herrera. Thanks especially to
Jakub for incredibly helpful and extensive testing.
 
Discussion: http://postgr.es/m/CA+TgmoYOYZfMCyOXFyC-P+-mdrZqm5pP2N7S-r0z3_402h9rsA@mail.gmail.com

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Waiting for PostgreSQL 17 – Allow \watch queries to stop on minimum rows returned

On 29th of August 2023, Daniel Gustafsson committed patch:

Allow \watch queries to stop on minimum rows returned
 
When running a repeat query with \watch in psql, it can be
helpful to be able to stop the watch process when the query
no longer returns the expected amount of rows.  An example
would be to watch for the presence of a certain event in
pg_stat_activity and stopping when the event is no longer
present, or to watch an index creation and stop when the
index is created.
 
This adds a min_rows=MIN parameter to \watch which can be
set to a non-negative integer, and the watch query will
stop executing when it returns less than MIN rows.
 
Author: Greg Sabino Mullane <htamfids@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/CAKAnmmKStATuddYxP71L+p0DHtp9Rvjze3XRoy0Dyw67VQ45UA@mail.gmail.com

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Waiting for PostgreSQL 17 – Generate new LOG for “trust” connections under log_connections

On 26th of August 2023, Michael Paquier committed patch:

Generate new LOG for "trust" connections under log_connections
 
Adding an extra LOG for connections that have not set an authn ID, like
when the "trust" authentication method is used, is useful for audit
purposes.
 
A couple of TAP tests for SSL and authentication need to be tweaked to
adapt to this new LOG generated, as some scenarios expected no logs but
they now get a hit.
 
Reported-by: Shaun Thomas
Author: Jacob Champion
Reviewed-by: Robert Haas, Michael Paquier
Discussion: https://postgr.es/m/CAFdbL1N7-GF-ZXKaB3XuGA+CkSmnjFvqb8hgjMnDfd+uhL2u-A@mail.gmail.com

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