Allow streaming replication configuration settings to be changed by reload (Sergei Kornilov)

Previously, a server restart was required to change primary_conninfo and primary_slot_name.

Allow WAL receivers to use a temporary replication slot when a permanent one is not specified (Peter Eisentraut, Sergei Kornilov)

This behavior can be enabled using wal_receiver_create_temp_slot.

Allow WAL storage for replication slots to be limited by max_slot_wal_keep_size (Kyotaro Horiguchi)

Replication slots that would require exceeding this value are marked invalid.

Allow standby promotion to cancel any requested pause (Fujii Masao)

Previously, promotion could not happen while the standby was in paused state.

Generate an error if recovery does not reach the specified recovery target (Leif Gunnar Erlandsen, Peter Eisentraut)

Previously, a standby would promote itself upon reaching the end of WAL, even if the target was not reached.

Allow control over how much memory is used by logical decoding before it is spilled to disk (Tomas Vondra, Dilip Kumar, Amit Kapila)

This is controlled by logical_decoding_work_mem.

Allow recovery to continue even if invalid pages are referenced by WAL (Fujii Masao)

This is enabled using ignore_invalid_pages.

Allow VACUUM to process a table's indexes in parallel (Masahiko Sawada, Amit Kapila)

The new PARALLEL option controls this.

Allow FETCH FIRST to use WITH TIES to return any additional rows that match the last result row (Surafel Temesgen)

Report planning-time buffer usage in EXPLAIN's BUFFER output (Julien Rouhaud)

Make CREATE TABLE LIKE propagate a CHECK constraint's NO INHERIT property to the created table (Ildar Musin, Chris Travers)

When using LOCK TABLE on a partitioned table, do not check permissions on the child tables (Amit Langote)

Allow OVERRIDING USER VALUE on inserts into identity columns (Dean Rasheed)

Add ALTER TABLE ... DROP EXPRESSION to allow removing the GENERATED property from a column (Peter Eisentraut)

Fix bugs in multi-step ALTER TABLE commands (Tom Lane)

IF NOT EXISTS clauses now work as expected, in that derived actions (such as index creation) do not execute if the column already exists. Also, certain cases of combining related actions into one ALTER TABLE now work when they did not before.

Add ALTER VIEW syntax to rename view columns (Fujii Masao)

Renaming view columns was already possible, but one had to write ALTER TABLE RENAME COLUMN, which is confusing.

Add ALTER TYPE options to modify a base type's TOAST properties and support functions (Tomas Vondra, Tom Lane)

Add CREATE DATABASE LOCALE option (Peter Eisentraut)

This combines the existing options LC_COLLATE and LC_CTYPE into a single option.

Allow DROP DATABASE to disconnect sessions using the target database, allowing the drop to succeed (Pavel Stehule, Amit Kapila)

This is enabled by the FORCE option.

Add structure member tg_updatedcols to allow C-language update triggers to know which column(s) were updated (Peter Eisentraut)

Add polymorphic data types for use by functions requiring compatible arguments (Pavel Stehule)

The new data types are anycompatible, anycompatiblearray, anycompatiblenonarray, and anycompatiblerange.

Add SQL data type xid8 to expose FullTransactionId (Thomas Munro)

The existing xid data type is only four bytes so it does not provide the transaction epoch.

Add data type regcollation and associated functions, to represent OIDs of collation objects (Julien Rouhaud)

Use the glibc version in some cases as a collation version identifier (Thomas Munro)

If the glibc version changes, a warning will be issued about possible corruption of collation-dependent indexes.

Add support for collation versions on Windows (Thomas Munro)

Allow ROW expressions to have their members extracted with suffix notation (Tom Lane)

For example, (ROW(4, 5.0)).f1 now returns 4.

Add alternate version of jsonb_set() with improved NULL handling (Andrew Dunstan)

The new function, jsonb_set_lax(), handles a NULL new value by either setting the specified key to a JSON null, deleting the key, raising an exception, or returning the jsonb value unmodified, as requested.

Add jsonpath .datetime() method (Nikita Glukhov, Teodor Sigaev, Oleg Bartunov, Alexander Korotkov)

This function allows JSON values to be converted to timestamps, which can then be processed in jsonpath expressions. This change also adds jsonpath functions that support time-zone-aware output.

Add SQL functions NORMALIZE() to normalize Unicode strings, and IS NORMALIZED to check for normalization (Peter Eisentraut)

Add min() and max() aggregates for pg_lsn (Fabrízio de Royes Mello)

These are particularly useful in monitoring queries.

Allow Unicode escapes, e.g., E'\unnnn' or U&'\nnnn', to specify any character available in the database encoding, even when the database encoding is not UTF-8 (Tom Lane)

Allow to_date() and to_timestamp() to recognize non-English month/day names (Juan José Santamaría Flecha, Tom Lane)

The names recognized are the same as those output by to_char() with the same format patterns.

Add datetime format patterns FF1 – FF6 to specify input or output of 1 to 6 fractional-second digits (Alexander Korotkov, Nikita Glukhov, Teodor Sigaev, Oleg Bartunov)

These patterns can be used by to_char(), to_timestamp(), and jsonpath's .datetime().

Add SSSSS datetime format pattern as an SQL-standard alias for SSSS (Nikita Glukhov, Alexander Korotkov)

Add function gen_random_uuid() to generate version-4 UUIDs (Peter Eisentraut)

Previously UUID generation functions were only available in the external modules uuid-ossp and pgcrypto.

Add greatest-common-denominator (gcd) and least-common-multiple (lcm) functions (Vik Fearing)

Improve the performance and accuracy of the numeric type's square root (sqrt) and natural log (ln) functions (Dean Rasheed)

Add function min_scale() that returns the number of digits to the right of the decimal point that are required to represent a numeric value with full accuracy (Pavel Stehule)

Add function trim_scale() to reduce the scale of a numeric value by removing trailing zeros (Pavel Stehule)

Add commutators of distance operators (Nikita Glukhov)

For example, previously only point <-> line was supported, now line <-> point works too.

Create xid8 versions of all transaction ID functions (Thomas Munro)

The old xid-based functions still exist, for backward compatibility.

Allow get_bit() and set_bit() to set bits beyond the first 256MB of a bytea value (Movead Li)

Allow advisory-lock functions to be used in some parallel operations (Tom Lane)

Add the ability to remove an object's dependency on an extension (Álvaro Herrera)

The object can be a function, materialized view, index, or trigger. The syntax is ALTER .. NO DEPENDS ON.

Improve performance of simple PL/pgSQL expressions (Tom Lane, Amit Langote)

Improve performance of PL/pgSQL functions that use immutable expressions (Konstantin Knizhnik)

Allow libpq clients to require channel binding for encrypted connections (Jeff Davis)

Using the libpq connection parameter channel_binding forces the other end of the TLS connection to prove it knows the user's password. This prevents man-in-the-middle attacks.

Add libpq connection parameters to control the minimum and maximum TLS version allowed for an encrypted connection (Daniel Gustafsson)

The settings are ssl_min_protocol_version and ssl_max_protocol_version. By default, the minimum TLS version is 1.2 (this represents a behavioral change from previous releases).

Allow use of passwords to unlock client certificates (Craig Ringer, Andrew Dunstan)

This is enabled by libpq's sslpassword connection parameter.

Allow libpq to use DER-encoded client certificates (Craig Ringer, Andrew Dunstan)

Fix ecpg's EXEC SQL elif directive to work correctly (Tom Lane)

Previously it behaved the same as endif followed by ifdef, so that a successful previous branch of the same if construct did not prevent expansion of the elif branch or following branches.

Generate backup manifests for base backups, and verify them (Robert Haas)

A new tool pg_verifybackup can verify backups.

Have pg_basebackup estimate the total backup size by default (Fujii Masao)

This computation allows pg_stat_progress_basebackup to show progress. If that is not needed, it can be disabled by using the --no-estimate-size option. Previously, this computation happened only if the --progress option was used.

Add an option to pg_rewind to configure standbys (Paul Guo, Jimmy Yih, Ashwin Agrawal)

This matches pg_basebackup's --write-recovery-conf option.

Allow pg_rewind to use the target cluster's restore_command to retrieve needed WAL (Alexey Kondratov)

This is enabled using the -c/--restore-target-wal option.

Have pg_rewind automatically run crash recovery before rewinding (Paul Guo, Jimmy Yih, Ashwin Agrawal)

This can be disabled by using --no-ensure-shutdown.

Increase the PREPARE TRANSACTION-related information reported by pg_waldump (Fujii Masao)

Add pg_waldump option --quiet to suppress non-error output (Andres Freund, Robert Haas)

Add pg_dump option --include-foreign-data to dump data from foreign servers (Luis Carril)

Allow vacuum commands run by vacuumdb to operate in parallel mode (Masahiko Sawada)

This is enabled with the new --parallel option.

Allow reindexdb to operate in parallel (Julien Rouhaud)

Parallel mode is enabled with the new --jobs option.

Allow dropdb to disconnect sessions using the target database, allowing the drop to succeed (Pavel Stehule)

This is enabled with the -f option.

Remove --adduser and --no-adduser from createuser (Alexander Lakhin)

The long-supported preferred options for this are called --superuser and --no-superuser.

Use the directory of the pg_upgrade program as the default --new-bindir setting when running pg_upgrade (Daniel Gustafsson)

Add a glossary to the documentation (Corey Huinker, Jürgen Purtz, Roger Harkavy, Álvaro Herrera)

Reformat tables containing function and operator information for better clarity (Tom Lane)

Upgrade to use DocBook 4.5 (Peter Eisentraut)

Add support for building on Visual Studio 2019 (Haribabu Kommi)

Add build support for MSYS2 (Peter Eisentraut)

Add compare_exchange and fetch_add assembly language code for Power PC compilers (Noah Misch)

Update Snowball stemmer dictionaries used by full text search (Panagiotis Mavrogiorgos)

This adds Greek stemming and improves Danish and French stemming.

Remove support for Windows 2000 (Michael Paquier)

Remove support for non-ELF BSD systems (Peter Eisentraut)

Remove support for Python versions 2.5.X and earlier (Peter Eisentraut)

Remove support for OpenSSL 0.9.8 and 1.0.0 (Michael Paquier)

Remove configure options --disable-float8-byval and --disable-float4-byval (Peter Eisentraut)

These were needed for compatibility with some version-zero C functions, but those are no longer supported.

Pass the query string to planner hook functions (Pascal Legrand, Julien Rouhaud)

Add TRUNCATE command hook (Yuli Khodorkovskiy)

Add TLS init hook (Andrew Dunstan)

Allow building with no predefined Unix-domain socket directory (Peter Eisentraut)

Reduce the probability of SysV resource key collision on Unix platforms (Tom Lane)

Use operating system functions to reliably erase memory that contains sensitive information (Peter Eisentraut)

For example, this is used for clearing passwords stored in memory.

Add headerscheck script to test C header-file compatibility (Tom Lane)

Implement internal lists as arrays, rather than a chain of cells (Tom Lane)

This improves performance for queries that access many objects.

Change the API for TS_execute() (Tom Lane, Pavel Borisov)

TS_execute callbacks must now provide ternary (yes/no/maybe) logic. Calculating NOT queries accurately is now the default.

Allow extensions to be specified as trusted (Tom Lane)

Such extensions can be installed in a database by users with database-level CREATE privileges, even if they are not superusers. This change also removes the pg_pltemplate system catalog.

Allow non-superusers to connect to postgres_fdw foreign servers without using a password (Craig Ringer)

Specifically, allow a superuser to set password_required to false for a user mapping. Care must still be taken to prevent non-superusers from using superuser credentials to connect to the foreign server.

Allow postgres_fdw to use certificate authentication (Craig Ringer)

Different users can use different certificates.

Allow sepgsql to control access to the TRUNCATE command (Yuli Khodorkovskiy)

Add extension bool_plperl which transforms SQL booleans to/from PL/Perl booleans (Ivan Panchenko)

Have pg_stat_statements treat SELECT ... FOR UPDATE commands as distinct from those without FOR UPDATE (Andrew Gierth, Vik Fearing)

Allow pg_stat_statements to optionally track the planning time of statements (Julien Rouhaud, Pascal Legrand, Thomas Munro, Fujii Masao)

Previously only execution time was tracked.

Overhaul ltree's lquery syntax to treat NOT (!) more logically (Filip Rembialkowski, Tom Lane, Nikita Glukhov)

Also allow non-* queries to use a numeric range ({}) of matches.

Add support for binary I/O of ltree, lquery, and ltxtquery types (Nino Floris)

Add an option to dict_int to ignore the sign of integers (Jeff Janes)

Add adminpack function pg_file_sync() to allow fsync'ing a file (Fujii Masao)

Add pageinspect functions to output t_infomask/t_infomask2 values in human-readable format (Craig Ringer, Sawada Masahiko, Michael Paquier)

Add B-tree index de-duplication processing columns to pageinspect output (Peter Geoghegan)