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E.1. Release 18 #

   E.1.1. Overview
   E.1.2. Migration to Version 18
   E.1.3. Changes
   E.1.4. Acknowledgments

   Release date: 2025-09-25

E.1.1. Overview #

   PostgreSQL 18 contains many new features and enhancements, including:
     * An asynchronous I/O (AIO) subsystem that can improve performance of
       sequential scans, bitmap heap scans, vacuums, and other operations.
     * pg_upgrade now retains optimizer statistics.
     * Support for "skip scan" lookups that allow using multicolumn B-tree
       indexes in more cases.
     * uuidv7() function for generating timestamp-ordered UUIDs.
     * Virtual generated columns that compute their values during read
       operations. This is now the default for generated columns.
     * OAuth authentication support.
     * OLD and NEW support for RETURNING clauses in INSERT, UPDATE,
       DELETE, and MERGE commands.
     * Temporal constraints, or constraints over ranges, for PRIMARY KEY,
       UNIQUE, and FOREIGN KEY constraints.

   The above items and other new features of PostgreSQL 18 are explained
   in more detail in the sections below.

E.1.2. Migration to Version 18 #

   A dump/restore using pg_dumpall or use of pg_upgrade or logical
   replication is required for those wishing to migrate data from any
   previous release. See Section 18.6 for general information on migrating
   to new major releases.

   Version 18 contains a number of changes that may affect compatibility
   with previous releases. Observe the following incompatibilities:
     * Change initdb default to enable data checksums (Greg Sabino
       Mullane) §
       Checksums can be disabled with the new initdb option
       --no-data-checksums. pg_upgrade requires matching cluster checksum
       settings, so this new option can be useful to upgrade non-checksum
       old clusters.
     * Change time zone abbreviation handling (Tom Lane) §
       The system will now favor the current session's time zone
       abbreviations before checking the server variable
       timezone_abbreviations. Previously timezone_abbreviations was
       checked first.
     * Deprecate MD5 password authentication (Nathan Bossart) §
       Support for MD5 passwords will be removed in a future major version
       release. CREATE ROLE and ALTER ROLE now emit deprecation warnings
       when setting MD5 passwords. These warnings can be disabled by
       setting the md5_password_warnings parameter to off.
     * Change VACUUM and ANALYZE to process the inheritance children of a
       parent (Michael Harris) §
       The previous behavior can be performed by using the new ONLY
       option.
     * Prevent COPY FROM from treating \. as an end-of-file marker when
       reading CSV files (Daniel Vérité, Tom Lane) § §
       psql will still treat \. as an end-of-file marker when reading CSV
       files from STDIN. Older psql clients connecting to PostgreSQL 18
       servers might experience \copy problems. This release also enforces
       that \. must appear alone on a line.
     * Disallow unlogged partitioned tables (Michael Paquier) §
       Previously ALTER TABLE SET [UN]LOGGED did nothing, and the creation
       of an unlogged partitioned table did not cause its children to be
       unlogged.
     * Execute AFTER triggers as the role that was active when trigger
       events were queued (Laurenz Albe) §
       Previously such triggers were run as the role that was active at
       trigger execution time (e.g., at COMMIT). This is significant for
       cases where the role is changed between queue time and transaction
       commit.
     * Remove non-functional support for rule privileges in GRANT/REVOKE
       (Fujii Masao) §
       These have been non-functional since PostgreSQL 8.2.
     * Remove column pg_backend_memory_contexts.parent (Melih Mutlu) §
       This is no longer needed since pg_backend_memory_contexts.path was
       added.
     * Change pg_backend_memory_contexts.level and
       pg_log_backend_memory_contexts() to be one-based (Melih Mutlu,
       Atsushi Torikoshi, David Rowley, Fujii Masao) § § §
       These were previously zero-based.
     * Change full text search to use the default collation provider of
       the cluster to read configuration files and dictionaries, rather
       than always using libc (Peter Eisentraut) §
       Clusters that default to non-libc collation providers (e.g., ICU,
       builtin) that behave differently than libc for characters processed
       by LC_CTYPE could observe changes in behavior of some full-text
       search functions, as well as the pg_trgm extension. When upgrading
       such clusters using pg_upgrade, it is recommended to reindex all
       indexes related to full-text search and pg_trgm after the upgrade.

E.1.3. Changes #

   Below you will find a detailed account of the changes between
   PostgreSQL 18 and the previous major release.

E.1.3.1. Server #

E.1.3.1.1. Optimizer #

     * Automatically remove some unnecessary table self-joins (Andrey
       Lepikhov, Alexander Kuzmenkov, Alexander Korotkov, Alena Rybakina)
       §
       This optimization can be disabled using server variable
       enable_self_join_elimination.
     * Convert some IN (VALUES ...) to x = ANY ... for better optimizer
       statistics (Alena Rybakina, Andrei Lepikhov) §
     * Allow transforming OR-clauses to arrays for faster index processing
       (Alexander Korotkov, Andrey Lepikhov) §
     * Speed up the processing of INTERSECT, EXCEPT, window aggregates,
       and view column aliases (Tom Lane, David Rowley) § § § §
     * Allow the keys of SELECT DISTINCT to be internally reordered to
       avoid sorting (Richard Guo) §
       This optimization can be disabled using enable_distinct_reordering.
     * Ignore GROUP BY columns that are functionally dependent on other
       columns (Zhang Mingli, Jian He, David Rowley) §
       If a GROUP BY clause includes all columns of a unique index, as
       well as other columns of the same table, those other columns are
       redundant and can be dropped from the grouping. This was already
       true for non-deferred primary keys.
     * Allow some HAVING clauses on GROUPING SETS to be pushed to WHERE
       clauses (Richard Guo) § § § §
       This allows earlier row filtering. This release also fixes some
       GROUPING SETS queries that used to return incorrect results.
     * Improve row estimates for generate_series() using numeric and
       timestamp values (David Rowley, Song Jinzhou) § §
     * Allow the optimizer to use Right Semi Join plans (Richard Guo) §
       Semi-joins are used when needing to find if there is at least one
       match.
     * Allow merge joins to use incremental sorts (Richard Guo) §
     * Improve the efficiency of planning queries accessing many
       partitions (Ashutosh Bapat, Yuya Watari, David Rowley) § §
     * Allow partitionwise joins in more cases, and reduce its memory
       usage (Richard Guo, Tom Lane, Ashutosh Bapat) § §
     * Improve cost estimates of partition queries (Nikita Malakhov,
       Andrei Lepikhov) §
     * Improve SQL-language function plan caching (Alexander Pyhalov, Tom
       Lane) § §
     * Improve handling of disabled optimizer features (Robert Haas) §

E.1.3.1.2. Indexes #

     * Allow skip scans of btree indexes (Peter Geoghegan) § §
       This allows multi-column btree indexes to be used in more cases
       such as when there are no restrictions on the first or early
       indexed columns (or there are non-equality ones), and there are
       useful restrictions on later indexed columns.
     * Allow non-btree unique indexes to be used as partition keys and in
       materialized views (Mark Dilger) § §
       The index type must still support equality.
     * Allow GIN indexes to be created in parallel (Tomas Vondra, Matthias
       van de Meent) §
     * Allow values to be sorted to speed range-type GiST and btree index
       builds (Bernd Helmle) §

E.1.3.1.3. General Performance #

     * Add an asynchronous I/O subsystem (Andres Freund, Thomas Munro,
       Nazir Bilal Yavuz, Melanie Plageman) § § § § § § § § § § §
       This feature allows backends to queue multiple read requests, which
       allows for more efficient sequential scans, bitmap heap scans,
       vacuums, etc. This is enabled by server variable io_method, with
       server variables io_combine_limit and io_max_combine_limit added to
       control it. This also enables effective_io_concurrency and
       maintenance_io_concurrency values greater than zero for systems
       without fadvise() support. The new system view pg_aios shows the
       file handles being used for asynchronous I/O.
     * Improve the locking performance of queries that access many
       relations (Tomas Vondra) §
     * Improve the performance and reduce memory usage of hash joins and
       GROUP BY (David Rowley, Jeff Davis) § § § § §
       This also improves hash set operations used by EXCEPT, and hash
       lookups of subplan values.
     * Allow normal vacuums to freeze some pages, even though they are
       all-visible (Melanie Plageman) § §
       This reduces the overhead of later full-relation freezing. The
       aggressiveness of this can be controlled by server variable and
       per-table setting vacuum_max_eager_freeze_failure_rate. Previously
       vacuum never processed all-visible pages until freezing was
       required.
     * Add server variable vacuum_truncate to control file truncation
       during VACUUM (Nathan Bossart, Gurjeet Singh) §
       A storage-level parameter with the same name and behavior already
       existed.
     * Increase server variables effective_io_concurrency's and
       maintenance_io_concurrency's default values to 16 (Melanie
       Plageman) § §
       This more accurately reflects modern hardware.

E.1.3.1.4. Monitoring #

     * Increase the logging granularity of server variable log_connections
       (Melanie Plageman) §
       This server variable was previously only boolean, which is still
       supported.
     * Add log_connections option to report the duration of connection
       stages (Melanie Plageman) §
     * Add log_line_prefix escape %L to output the client IP address (Greg
       Sabino Mullane) §
     * Add server variable log_lock_failures to log lock acquisition
       failures (Yuki Seino, Fujii Masao) § §
       Specifically it reports SELECT ... NOWAIT lock failures.
     * Modify pg_stat_all_tables and its variants to report the time spent
       in VACUUM, ANALYZE, and their automatic variants (Sami Imseih) §
       The new columns are total_vacuum_time, total_autovacuum_time,
       total_analyze_time, and total_autoanalyze_time.
     * Add delay time reporting to VACUUM and ANALYZE (Bertrand Drouvot,
       Nathan Bossart) § §
       This information appears in the server log, the system views
       pg_stat_progress_vacuum and pg_stat_progress_analyze, and the
       output of VACUUM and ANALYZE when in VERBOSE mode; tracking must be
       enabled with the server variable track_cost_delay_timing.
     * Add WAL, CPU, and average read statistics output to ANALYZE VERBOSE
       (Anthonin Bonnefoy) § §
     * Add full WAL buffer count to VACUUM/ANALYZE (VERBOSE) and
       autovacuum log output (Bertrand Drouvot) §
     * Add per-backend I/O statistics reporting (Bertrand Drouvot) § §
       The statistics are accessed via pg_stat_get_backend_io().
       Per-backend I/O statistics can be cleared via
       pg_stat_reset_backend_stats().
     * Add pg_stat_io columns to report I/O activity in bytes (Nazir Bilal
       Yavuz) §
       The new columns are read_bytes, write_bytes, and extend_bytes. The
       op_bytes column, which always equaled BLCKSZ, has been removed.
     * Add WAL I/O activity rows to pg_stat_io (Nazir Bilal Yavuz,
       Bertrand Drouvot, Michael Paquier) § § §
       This includes WAL receiver activity and a wait event for such
       writes.
     * Change server variable track_wal_io_timing to control tracking WAL
       timing in pg_stat_io instead of pg_stat_wal (Bertrand Drouvot) §
     * Remove read/sync columns from pg_stat_wal (Bertrand Drouvot) § §
       This removes columns wal_write, wal_sync, wal_write_time, and
       wal_sync_time.
     * Add function pg_stat_get_backend_wal() to return per-backend WAL
       statistics (Bertrand Drouvot) §
       Per-backend WAL statistics can be cleared via
       pg_stat_reset_backend_stats().
     * Add function pg_ls_summariesdir() to specifically list the contents
       of PGDATA/pg_wal/summaries (Yushi Ogiwara) §
     * Add column pg_stat_checkpointer.num_done to report the number of
       completed checkpoints (Anton A. Melnikov) §
       Columns num_timed and num_requested count both completed and
       skipped checkpoints.
     * Add column pg_stat_checkpointer.slru_written to report SLRU buffers
       written (Nitin Jadhav) §
       Also, modify the checkpoint server log message to report separate
       shared buffer and SLRU buffer values.
     * Add columns to pg_stat_database to report parallel worker activity
       (Benoit Lobréau) §
       The new columns are parallel_workers_to_launch and
       parallel_workers_launched.
     * Have query id computation of constant lists consider only the first
       and last constants (Dmitry Dolgov, Sami Imseih) § § §
       Jumbling is used by pg_stat_statements.
     * Adjust query id computations to group together queries using the
       same relation name (Michael Paquier, Sami Imseih) §
       This is true even if the tables in different schemas have different
       column names.
     * Add column pg_backend_memory_contexts.type to report the type of
       memory context (David Rowley) §
     * Add column pg_backend_memory_contexts.path to show memory context
       parents (Melih Mutlu) §

E.1.3.1.5. Privileges #

     * Add function pg_get_acl() to retrieve database access control
       details (Joel Jacobson) § §
     * Add function has_largeobject_privilege() to check large object
       privileges (Yugo Nagata) §
     * Allow ALTER DEFAULT PRIVILEGES to define large object default
       privileges (Takatsuka Haruka, Yugo Nagata, Laurenz Albe) §
     * Add predefined role pg_signal_autovacuum_worker (Kirill Reshke) §
       This allows sending signals to autovacuum workers.

E.1.3.1.6. Server Configuration #

     * Add support for the OAuth authentication method (Jacob Champion,
       Daniel Gustafsson, Thomas Munro) §
       This adds an oauth authentication method to pg_hba.conf, libpq
       OAuth options, a server variable oauth_validator_libraries to load
       token validation libraries, and a configure flag --with-libcurl to
       add the required compile-time libraries.
     * Add server variable ssl_tls13_ciphers to allow specification of
       multiple colon-separated TLSv1.3 cipher suites (Erica Zhang, Daniel
       Gustafsson) §
     * Change server variable ssl_groups's default to include elliptic
       curve X25519 (Daniel Gustafsson, Jacob Champion) §
     * Rename server variable ssl_ecdh_curve to ssl_groups and allow
       multiple colon-separated ECDH curves to be specified (Erica Zhang,
       Daniel Gustafsson) §
       The previous name still works.
     * Make cancel request keys 256 bits (Heikki Linnakangas, Jelte
       Fennema-Nio) § §
       This is only possible when the server and client support wire
       protocol version 3.2, introduced in this release.
     * Add server variable autovacuum_worker_slots to specify the maximum
       number of background workers (Nathan Bossart) §
       With this variable set, autovacuum_max_workers can be adjusted at
       runtime up to this maximum without a server restart.
     * Allow specification of the fixed number of dead tuples that will
       trigger an autovacuum (Nathan Bossart, Frédéric Yhuel) §
       The server variable is autovacuum_vacuum_max_threshold. Percentages
       are still used for triggering.
     * Change server variable max_files_per_process to limit only files
       opened by a backend (Andres Freund) §
       Previously files opened by the postmaster were also counted toward
       this limit.
     * Add server variable num_os_semaphores to report the required number
       of semaphores (Nathan Bossart) §
       This is useful for operating system configuration.
     * Add server variable extension_control_path to specify the location
       of extension control files (Peter Eisentraut, Matheus Alcantara) §
       §

E.1.3.1.7. Streaming Replication and Recovery #

     * Allow inactive replication slots to be automatically invalidated
       using server variable idle_replication_slot_timeout (Nisha Moond,
       Bharath Rupireddy) §
     * Add server variable max_active_replication_origins to control the
       maximum active replication origins (Euler Taveira) §
       This was previously controlled by max_replication_slots, but this
       new setting allows a higher origin count in cases where fewer slots
       are required.

E.1.3.1.8. Logical Replication #

     * Allow the values of generated columns to be logically replicated
       (Shubham Khanna, Vignesh C, Zhijie Hou, Shlok Kyal, Peter Smith) §
       § § §
       If the publication specifies a column list, all specified columns,
       generated and non-generated, are published. Without a specified
       column list, publication option publish_generated_columns controls
       whether generated columns are published. Previously generated
       columns were not replicated and the subscriber had to compute the
       values if possible; this is particularly useful for non-PostgreSQL
       subscribers which lack such a capability.
     * Change the default CREATE SUBSCRIPTION streaming option from off to
       parallel (Vignesh C) §
     * Allow ALTER SUBSCRIPTION to change the replication slot's two-phase
       commit behavior (Hayato Kuroda, Ajin Cherian, Amit Kapila, Zhijie
       Hou) § §
     * Log conflicts while applying logical replication changes (Zhijie
       Hou, Nisha Moond) § § § § §
       Also report in new columns of pg_stat_subscription_stats.

E.1.3.2. Utility Commands #

     * Allow generated columns to be virtual, and make them the default
       (Peter Eisentraut, Jian He, Richard Guo, Dean Rasheed) § § §
       Virtual generated columns generate their values when the columns
       are read, not written. The write behavior can still be specified
       via the STORED option.
     * Add OLD/NEW support to RETURNING in DML queries (Dean Rasheed) §
       Previously RETURNING only returned new values for INSERT and
       UPDATE, and old values for DELETE; MERGE would return the
       appropriate value for the internal query executed. This new syntax
       allows the RETURNING list of INSERT/UPDATE/DELETE/MERGE to
       explicitly return old and new values by using the special aliases
       old and new. These aliases can be renamed to avoid identifier
       conflicts.
     * Allow foreign tables to be created like existing local tables
       (Zhang Mingli) §
       The syntax is CREATE FOREIGN TABLE ... LIKE.
     * Allow LIKE with nondeterministic collations (Peter Eisentraut) §
     * Allow text position search functions with nondeterministic
       collations (Peter Eisentraut) §
       These used to generate an error.
     * Add builtin collation provider PG_UNICODE_FAST (Jeff Davis) §
       This locale supports case mapping, but sorts in code point order,
       not natural language order.
     * Allow VACUUM and ANALYZE to process partitioned tables without
       processing their children (Michael Harris) §
       This is enabled with the new ONLY option. This is useful since
       autovacuum does not process partitioned tables, just its children.
     * Add functions to modify per-relation and per-column optimizer
       statistics (Corey Huinker) § § §
       The functions are pg_restore_relation_stats(),
       pg_restore_attribute_stats(), pg_clear_relation_stats(), and
       pg_clear_attribute_stats().
     * Add server variable file_copy_method to control the file copying
       method (Nazir Bilal Yavuz) §
       This controls whether CREATE DATABASE ... STRATEGY=FILE_COPY and
       ALTER DATABASE ... SET TABLESPACE uses file copy or clone.

E.1.3.2.1. Constraints #

     * Allow the specification of non-overlapping PRIMARY KEY, UNIQUE, and
       foreign key constraints (Paul A. Jungwirth) § §
       This is specified by WITHOUT OVERLAPS for PRIMARY KEY and UNIQUE,
       and by PERIOD for foreign keys, all applied to the last specified
       column.
     * Allow CHECK and foreign key constraints to be specified as NOT
       ENFORCED (Amul Sul) § §
       This also adds column pg_constraint.conenforced.
     * Require primary/foreign key relationships to use either
       deterministic collations or the the same nondeterministic
       collations (Peter Eisentraut) §
       The restore of a pg_dump, also used by pg_upgrade, will fail if
       these requirements are not met; schema changes must be made for
       these upgrade methods to succeed.
     * Store column NOT NULL specifications in pg_constraint (Álvaro
       Herrera, Bernd Helmle) § §
       This allows names to be specified for NOT NULL constraint. This
       also adds NOT NULL constraints to foreign tables and NOT NULL
       inheritance control to local tables.
     * Allow ALTER TABLE to set the NOT VALID attribute of NOT NULL
       constraints (Rushabh Lathia, Jian He) §
     * Allow modification of the inheritability of NOT NULL constraints
       (Suraj Kharage, Álvaro Herrera) § §
       The syntax is ALTER TABLE ... ALTER CONSTRAINT ... [NO] INHERIT.
     * Allow NOT VALID foreign key constraints on partitioned tables (Amul
       Sul) §
     * Allow dropping of constraints ONLY on partitioned tables (Álvaro
       Herrera) §
       This was previously erroneously prohibited.

E.1.3.2.2. COPY #

     * Add REJECT_LIMIT to control the number of invalid rows COPY FROM
       can ignore (Atsushi Torikoshi) §
       This is available when ON_ERROR = 'ignore'.
     * Allow COPY TO to copy rows from populated materialized views (Jian
       He) §
     * Add COPY LOG_VERBOSITY level silent to suppress log output of
       ignored rows (Atsushi Torikoshi) §
       This new level suppresses output for discarded input rows when
       on_error = 'ignore'.
     * Disallow COPY FREEZE on foreign tables (Nathan Bossart) §
       Previously, the COPY worked but the FREEZE was ignored, so disallow
       this command.

E.1.3.2.3. EXPLAIN #

     * Automatically include BUFFERS output in EXPLAIN ANALYZE (Guillaume
       Lelarge, David Rowley) §
     * Add full WAL buffer count to EXPLAIN (WAL) output (Bertrand
       Drouvot) §
     * In EXPLAIN ANALYZE, report the number of index lookups used per
       index scan node (Peter Geoghegan) §
     * Modify EXPLAIN to output fractional row counts (Ibrar Ahmed, Ilia
       Evdokimov, Robert Haas) § §
     * Add memory and disk usage details to Material, Window Aggregate,
       and common table expression nodes to EXPLAIN output (David Rowley,
       Tatsuo Ishii) § § § §
     * Add details about window function arguments to EXPLAIN output (Tom
       Lane) §
     * Add Parallel Bitmap Heap Scan worker cache statistics to EXPLAIN
       ANALYZE (David Geier, Heikki Linnakangas, Donghang Lin, Alena
       Rybakina, David Rowley) §
     * Indicate disabled nodes in EXPLAIN ANALYZE output (Robert Haas,
       David Rowley, Laurenz Albe) § § §

E.1.3.3. Data Types #

     * Improve Unicode full case mapping and conversion (Jeff Davis) § §
       This adds the ability to do conditional and title case mapping, and
       case map single characters to multiple characters.
     * Allow jsonb null values to be cast to scalar types as NULL (Tom
       Lane) §
       Previously such casts generated an error.
     * Add optional parameter to json{b}_strip_nulls to allow removal of
       null array elements (Florents Tselai) §
     * Add function array_sort() which sorts an array's first dimension
       (Junwang Zhao, Jian He) §
     * Add function array_reverse() which reverses an array's first
       dimension (Aleksander Alekseev) §
     * Add function reverse() to reverse bytea bytes (Aleksander Alekseev)
       §
     * Allow casting between integer types and bytea (Aleksander Alekseev)
       §
       The integer values are stored as bytea two's complement values.
     * Update Unicode data to Unicode 16.0.0 (Peter Eisentraut) §
     * Add full text search stemming for Estonian (Tom Lane) §
     * Improve the XML error codes to more closely match the SQL standard
       (Tom Lane) §
       These errors are reported via SQLSTATE.

E.1.3.4. Functions #

     * Add function casefold() to allow for more sophisticated
       case-insensitive matching (Jeff Davis) §
       This allows more accurate comparisons, i.e., a character can have
       multiple upper or lower case equivalents, or upper or lower case
       conversion changes the number of characters.
     * Allow MIN()/MAX() aggregates on arrays and composite types
       (Aleksander Alekseev, Marat Buharov) § §
     * Add a WEEK option to EXTRACT() (Tom Lane) §
     * Improve the output EXTRACT(QUARTER ...) for negative values (Tom
       Lane) §
     * Add roman numeral support to to_number() (Hunaid Sohail) §
       This is accessed via the RN pattern.
     * Add UUID version 7 generation function uuidv7() (Andrey Borodin) §
       This UUID value is temporally sortable. Function alias uuidv4() has
       been added to explicitly generate version 4 UUIDs.
     * Add functions crc32() and crc32c() to compute CRC values
       (Aleksander Alekseev) §
     * Add math functions gamma() and lgamma() (Dean Rasheed) §
     * Allow => syntax for named cursor arguments in PL/pgSQL (Pavel
       Stehule) §
       We previously only accepted :=.
     * Allow
       regexp_match[es]()/regexp_like()/regexp_replace()/regexp_count()/re
       gexp_instr()/regexp_substr()/regexp_split_to_table()/regexp_split_t
       o_array() to use named arguments (Jian He) §

E.1.3.5. libpq #

     * Add function PQfullProtocolVersion() to report the full, including
       minor, protocol version number (Jacob Champion, Jelte Fennema-Nio)
       §
     * Add libpq connection parameters and environment variables to
       specify the minimum and maximum acceptable protocol version for
       connections (Jelte Fennema-Nio) § §
     * Report search_path changes to the client (Alexander Kukushkin,
       Jelte Fennema-Nio, Tomas Vondra) § §
     * Add PQtrace() output for all message types, including
       authentication (Jelte Fennema-Nio) § § § § §
     * Add libpq connection parameter sslkeylogfile which dumps out SSL
       key material (Abhishek Chanda, Daniel Gustafsson) §
       This is useful for debugging.
     * Modify some libpq function signatures to use int64_t (Thomas Munro)
       §
       These previously used pg_int64, which is now deprecated.

E.1.3.6. psql #

     * Allow psql to parse, bind, and close named prepared statements
       (Anthonin Bonnefoy, Michael Paquier) § §
       This is accomplished with new commands \parse, \bind_named, and
       \close_prepared.
     * Add psql backslash commands to allowing issuance of pipeline
       queries (Anthonin Bonnefoy) § § §
       The new commands are \startpipeline, \syncpipeline, \sendpipeline,
       \endpipeline, \flushrequest, \flush, and \getresults.
     * Allow adding pipeline status to the psql prompt and add related
       state variables (Anthonin Bonnefoy) §
       The new prompt character is %P and the new psql variables are
       PIPELINE_SYNC_COUNT, PIPELINE_COMMAND_COUNT, and
       PIPELINE_RESULT_COUNT.
     * Allow adding the connection service name to the psql prompt or
       access it via psql variable (Michael Banck) §
     * Add psql option to use expanded mode on all list commands (Dean
       Rasheed) §
       Adding backslash suffix x enables this.
     * Change psql's \conninfo to use tabular format and include more
       information (Álvaro Herrera, Maiquel Grassi, Hunaid Sohail) §
     * Add function's leakproof indicator to psql's \df+, \do+, \dAo+, and
       \dC+ outputs (Yugo Nagata) §
     * Add access method details for partitioned relations in \dP+ (Justin
       Pryzby) §
     * Add default_version to the psql \dx extension output (Magnus
       Hagander) §
     * Add psql variable WATCH_INTERVAL to set the default \watch wait
       time (Daniel Gustafsson) §

E.1.3.7. Server Applications #

     * Change initdb to default to enabling checksums (Greg Sabino
       Mullane) § §
       The new initdb option --no-data-checksums disables checksums.
     * Add initdb option --no-sync-data-files to avoid syncing heap/index
       files (Nathan Bossart) §
       initdb option --no-sync is still available to avoid syncing any
       files.
     * Add vacuumdb option --missing-stats-only to compute only missing
       optimizer statistics (Corey Huinker, Nathan Bossart) § §
       This option can only be run by superusers and can only be used with
       options --analyze-only and --analyze-in-stages.
     * Add pg_combinebackup option -k/--link to enable hard linking
       (Israel Barth Rubio, Robert Haas) §
       Only some files can be hard linked. This should not be used if the
       backups will be used independently.
     * Allow pg_verifybackup to verify tar-format backups (Amul Sul) §
     * If pg_rewind's --source-server specifies a database name, use it in
       --write-recovery-conf output (Masahiko Sawada) §
     * Add pg_resetwal option --char-signedness to change the default char
       signedness (Masahiko Sawada) §

E.1.3.7.1. pg_dump/pg_dumpall/pg_restore #

     * Add pg_dump option --statistics (Jeff Davis) § §
     * Add pg_dump and pg_dumpall option --sequence-data to dump sequence
       data that would normally be excluded (Nathan Bossart) § §
     * Add pg_dump, pg_dumpall, and pg_restore options --statistics-only,
       --no-statistics, --no-data, and --no-schema (Corey Huinker, Jeff
       Davis) §
     * Add option --no-policies to disable row level security policy
       processing in pg_dump, pg_dumpall, pg_restore (Nikolay Samokhvalov)
       §
       This is useful for migrating to systems with different policies.

E.1.3.7.2. pg_upgrade #

     * Allow pg_upgrade to preserve optimizer statistics (Corey Huinker,
       Jeff Davis, Nathan Bossart) § § § §
       Extended statistics are not preserved. Also add pg_upgrade option
       --no-statistics to disable statistics preservation.
     * Allow pg_upgrade to process database checks in parallel (Nathan
       Bossart) § § § § § § § § § § §
       This is controlled by the existing --jobs option.
     * Add pg_upgrade option --swap to swap directories rather than copy,
       clone, or link files (Nathan Bossart) §
       This mode is potentially the fastest.
     * Add pg_upgrade option --set-char-signedness to set the default char
       signedness of new cluster (Masahiko Sawada) § §
       This is to handle cases where a pre-PostgreSQL 18 cluster's default
       CPU signedness does not match the new cluster.

E.1.3.7.3. Logical Replication Applications #

     * Add pg_createsubscriber option --all to create logical replicas for
       all databases (Shubham Khanna) §
     * Add pg_createsubscriber option --clean to remove publications
       (Shubham Khanna) § §
     * Add pg_createsubscriber option --enable-two-phase to enable
       prepared transactions (Shubham Khanna) §
     * Add pg_recvlogical option --enable-failover to specify failover
       slots (Hayato Kuroda) §
       Also add option --enable-two-phase as a synonym for --two-phase,
       and deprecate the latter.
     * Allow pg_recvlogical --drop-slot to work without --dbname (Hayato
       Kuroda) §

E.1.3.8. Source Code #

     * Separate the loading and running of injection points (Michael
       Paquier, Heikki Linnakangas) § §
       Injection points can now be created, but not run, via
       INJECTION_POINT_LOAD(), and such injection points can be run via
       INJECTION_POINT_CACHED().
     * Support runtime arguments in injection points (Michael Paquier) §
     * Allow inline injection point test code with
       IS_INJECTION_POINT_ATTACHED() (Heikki Linnakangas) §
     * Improve the performance of processing long JSON strings using SIMD
       (Single Instruction Multiple Data) (David Rowley) §
     * Speed up CRC32C calculations using x86 AVX-512 instructions
       (Raghuveer Devulapalli, Paul Amonson) §
     * Add ARM Neon and SVE CPU intrinsics for popcount (integer bit
       counting) (Chiranmoy Bhattacharya, Devanga Susmitha, Rama Malladi)
       § §
     * Improve the speed of numeric multiplication and division (Joel
       Jacobson, Dean Rasheed) § § § §
     * Add configure option --with-libnuma to enable NUMA awareness (Jakub
       Wartak, Bertrand Drouvot) § § §
       The function pg_numa_available() reports on NUMA awareness, and
       system views pg_shmem_allocations_numa and pg_buffercache_numa
       which report on shared memory distribution across NUMA nodes.
     * Add TOAST table to pg_index to allow for very large expression
       indexes (Nathan Bossart) §
     * Remove column pg_attribute.attcacheoff (David Rowley) §
     * Add column pg_class.relallfrozen (Melanie Plageman) §
     * Add amgettreeheight, amconsistentequality, and amconsistentordering
       to the index access method API (Mark Dilger) § §
     * Add GiST support function stratnum() (Paul A. Jungwirth) §
     * Record the default CPU signedness of char in pg_controldata
       (Masahiko Sawada) §
     * Add support for Python "Limited API" in PL/Python (Peter
       Eisentraut) § §
       This helps prevent problems caused by Python 3.x version
       mismatches.
     * Change the minimum supported Python version to 3.6.8 (Jacob
       Champion) §
     * Remove support for OpenSSL versions older than 1.1.1 (Daniel
       Gustafsson) § §
     * If LLVM is enabled, require version 14 or later (Thomas Munro) §
     * Add macro PG_MODULE_MAGIC_EXT to allow extensions to report their
       name and version (Andrei Lepikhov) §
       This information can be access via the new function
       pg_get_loaded_modules().
     * Document that SPI_connect()/SPI_connect_ext() always returns
       success (SPI_OK_CONNECT) (Stepan Neretin) §
       Errors are always reported via ereport().
     * Add documentation section about API and ABI compatibility (David
       Wheeler, Peter Eisentraut) §
     * Remove the experimental designation of Meson builds on Windows
       (Aleksander Alekseev) §
     * Remove configure options --disable-spinlocks and --disable-atomics
       (Thomas Munro) § §
       Thirty-two-bit atomic operations are now required.
     * Remove support for the HPPA/PA-RISC architecture (Tom Lane) §

E.1.3.9. Additional Modules #

     * Add extension pg_logicalinspect to inspect logical snapshots
       (Bertrand Drouvot) §
     * Add extension pg_overexplain which adds debug details to EXPLAIN
       output (Robert Haas) §
     * Add output columns to postgres_fdw_get_connections() (Hayato
       Kuroda, Sagar Dilip Shedge) § § § §
       New output column used_in_xact indicates if the foreign data
       wrapper is being used by a current transaction, closed indicates if
       it is closed, user_name indicates the user name, and
       remote_backend_pid indicates the remote backend process identifier.
     * Allow SCRAM authentication from the client to be passed to
       postgres_fdw servers (Matheus Alcantara, Peter Eisentraut) §
       This avoids storing postgres_fdw authentication information in the
       database, and is enabled with the postgres_fdw
       use_scram_passthrough connection option. libpq uses new connection
       parameters scram_client_key and scram_server_key.
     * Allow SCRAM authentication from the client to be passed to dblink
       servers (Matheus Alcantara) §
     * Add on_error and log_verbosity options to file_fdw (Atsushi
       Torikoshi) §
       These control how file_fdw handles and reports invalid file rows.
     * Add reject_limit to control the number of invalid rows file_fdw can
       ignore (Atsushi Torikoshi) §
       This is active when ON_ERROR = 'ignore'.
     * Add configurable variable min_password_length to passwordcheck
       (Emanuele Musella, Maurizio Boriani) §
       This controls the minimum password length.
     * Have pgbench report the number of failed, retried, or skipped
       transactions in per-script reports (Yugo Nagata) §
     * Add isn server variable weak to control invalid check digit
       acceptance (Viktor Holmberg) §
       This was previously only controlled by function isn_weak().
     * Allow values to be sorted to speed btree_gist index builds (Bernd
       Helmle, Andrey Borodin) §
     * Add amcheck check function gin_index_check() to verify GIN indexes
       (Grigory Kryachko, Heikki Linnakangas, Andrey Borodin) §
     * Add functions pg_buffercache_evict_relation() and
       pg_buffercache_evict_all() to evict unpinned shared buffers (Nazir
       Bilal Yavuz) §
       The existing function pg_buffercache_evict() now returns the buffer
       flush status.
     * Allow extensions to install custom EXPLAIN options (Robert Haas,
       Sami Imseih) § § §
     * Allow extensions to use the server's cumulative statistics API
       (Michael Paquier) § §

E.1.3.9.1. pg_stat_statements #

     * Allow the queries of CREATE TABLE AS and DECLARE to be tracked by
       pg_stat_statements (Anthonin Bonnefoy) §
       They are also now assigned query ids.
     * Allow the parameterization of SET values in pg_stat_statements
       (Greg Sabino Mullane, Michael Paquier) §
       This reduces the bloat caused by SET statements with differing
       constants.
     * Add pg_stat_statements columns to report parallel activity
       (Guillaume Lelarge) §
       The new columns are parallel_workers_to_launch and
       parallel_workers_launched.
     * Add pg_stat_statements.wal_buffers_full to report full WAL buffers
       (Bertrand Drouvot) §

E.1.3.9.2. pgcrypto #

     * Add pgcrypto algorithms sha256crypt and sha512crypt (Bernd Helmle)
       §
     * Add CFB mode to pgcrypto encryption and decryption (Umar Hayat) §
     * Add function fips_mode() to report the server's FIPS mode (Daniel
       Gustafsson) §
     * Add pgcrypto server variable builtin_crypto_enabled to allow
       disabling builtin non-FIPS mode cryptographic functions (Daniel
       Gustafsson, Joe Conway) §
       This is useful for guaranteeing FIPS mode behavior.

E.1.4. Acknowledgments #

   The following individuals (in alphabetical order) have contributed to
   this release as patch authors, committers, reviewers, testers, or
   reporters of issues.
   Abhishek Chanda
   Adam Guo
   Adam Rauch
   Aidar Imamov
   Ajin Cherian
   Alastair Turner
   Alec Cozens
   Aleksander Alekseev
   Alena Rybakina
   Alex Friedman
   Alex Richman
   Alexander Alehin
   Alexander Borisov
   Alexander Korotkov
   Alexander Kozhemyakin
   Alexander Kukushkin
   Alexander Kuzmenkov
   Alexander Kuznetsov
   Alexander Lakhin
   Alexander Pyhalov
   Alexandra Wang
   Alexey Dvoichenkov
   Alexey Makhmutov
   Alexey Shishkin
   Ali Akbar
   Álvaro Herrera
   Álvaro Mongil
   Amit Kapila
   Amit Langote
   Amul Sul
   Andreas Karlsson
   Andreas Scherbaum
   Andreas Ulbrich
   Andrei Lepikhov
   Andres Freund
   Andrew
   Andrew Bille
   Andrew Dunstan
   Andrew Jackson
   Andrew Kane
   Andrew Watkins
   Andrey Borodin
   Andrey Chudnovsky
   Andrey Rachitskiy
   Andrey Rudometov
   Andy Alsup
   Andy Fan
   Anthonin Bonnefoy
   Anthony Hsu
   Anthony Leung
   Anton Melnikov
   Anton Voloshin
   Antonin Houska
   Antti Lampinen
   Arseniy Mukhin
   Artur Zakirov
   Arun Thirupathi
   Ashutosh Bapat
   Asphator
   Atsushi Torikoshi
   Avi Weinberg
   Aya Iwata
   Ayush Tiwari
   Ayush Vatsa
   Bastien Roucariès
   Ben Peachey Higdon
   Benoit Lobréau
   Bernd Helmle
   Bernd Reiß
   Bernhard Wiedemann
   Bertrand Drouvot
   Bertrand Mamasam
   Bharath Rupireddy
   Bogdan Grigorenko
   Boyu Yang
   Braulio Fdo Gonzalez
   Bruce Momjian
   Bykov Ivan
   Cameron Vogt
   Cary Huang
   Cédric Villemain
   Cees van Zeeland
   ChangAo Chen
   Chao Li
   Chapman Flack
   Charles Samborski
   Chengwen Wu
   Chengxi Sun
   Chiranmoy Bhattacharya
   Chris Gooch
   Christian Charukiewicz
   Christoph Berg
   Christophe Courtois
   Christopher Inokuchi
   Clemens Ruck
   Corey Huinker
   Craig Milhiser
   Crisp Lee
   Dagfinn Ilmari Mannsåker
   Daniel Elishakov
   Daniel Gustafsson
   Daniel Vérité
   Daniel Westermann
   Daniele Varrazzo
   Daniil Davydov
   Daria Shanina
   Dave Cramer
   Dave Page
   David Benjamin
   David Christensen
   David Fiedler
   David G. Johnston
   David Geier
   David Rowley
   David Steele
   David Wheeler
   David Zhang
   Davinder Singh
   Dean Rasheed
   Devanga Susmitha
   Devrim Gündüz
   Dian Fay
   Dilip Kumar
   Dimitrios Apostolou
   Dipesh Dhameliya
   Dmitrii Bondar
   Dmitry Dolgov
   Dmitry Koval
   Dmitry Kovalenko
   Dmitry Yurichev
   Dominique Devienne
   Donghang Lin
   Dorjpalam Batbaatar
   Drew Callahan
   Duncan Sands
   Dwayne Towell
   Dzmitry Jachnik
   Egor Chindyaskin
   Egor Rogov
   Emanuel Ionescu
   Emanuele Musella
   Emre Hasegeli
   Eric Cyr
   Erica Zhang
   Erik Nordström
   Erik Rijkers
   Erik Wienhold
   Erki Eessaar
   Ethan Mertz
   Etienne LAFARGE
   Etsuro Fujita
   Euler Taveira
   Evan Si
   Evgeniy Gorbanev
   Fabio R. Sluzala
   Fabrízio de Royes Mello
   Feike Steenbergen
   Feliphe Pozzer
   Felix
   Fire Emerald
   Florents Tselai
   Francesco Degrassi
   Frank Streitzig
   Frédéric Yhuel
   Fredrik Widlert
   Gabriele Bartolini
   Gavin Panella
   Geoff Winkless
   George MacKerron
   Gilles Darold
   Grant Gryczan
   Greg Burd
   Greg Sabino Mullane
   Greg Stark
   Grigory Kryachko
   Guillaume Lelarge
   Gunnar Morling
   Gunnar Wagner
   Gurjeet Singh
   Haifang Wang
   Hajime Matsunaga
   Hamid Akhtar
   Hannu Krosing
   Hari Krishna Sunder
   Haruka Takatsuka
   Hayato Kuroda
   Heikki Linnakangas
   Hironobu Suzuki
   Holger Jakobs
   Hubert Lubaczewski
   Hugo Dubois
   Hugo Zhang
   Hunaid Sohail
   Hywel Carver
   Ian Barwick
   Ibrar Ahmed
   Igor Gnatyuk
   Igor Korot
   Ilia Evdokimov
   Ilya Gladyshev
   Ilyasov Ian
   Imran Zaheer
   Isaac Morland
   Israel Barth Rubio
   Ivan Kush
   Jacob Brazeal
   Jacob Champion
   Jaime Casanova
   Jakob Egger
   Jakub Wartak
   James Coleman
   James Hunter
   Jan Behrens
   Japin Li
   Jason Smith
   Jayesh Dehankar
   Jeevan Chalke
   Jeff Davis
   Jehan-Guillaume de Rorthais
   Jelte Fennema-Nio
   Jian He
   Jianghua Yang
   Jiao Shuntian
   Jim Jones
   Jim Nasby
   Jingtang Zhang
   Jingzhou Fu
   Joe Conway
   Joel Jacobson
   John Hutchins
   John Naylor
   Jonathan Katz
   Jorge Solórzano
   José Villanova
   Josef Šimánek
   Joseph Koshakow
   Julien Rouhaud
   Junwang Zhao
   Justin Pryzby
   Kaido Vaikla
   Kaimeh
   Karina Litskevich
   Karthik S
   Kartyshov Ivan
   Kashif Zeeshan
   Keisuke Kuroda
   Kevin Hale Boyes
   Kevin K Biju
   Kirill Reshke
   Kirill Zdornyy
   Koen De Groote
   Koichi Suzuki
   Koki Nakamura
   Konstantin Knizhnik
   Kouhei Sutou
   Kuntal Ghosh
   Kyotaro Horiguchi
   Lakshmi Narayana Velayudam
   Lars Kanis
   Laurence Parry
   Laurenz Albe
   Lele Gaifax
   Li Yong
   Lilian Ontowhee
   Lingbin Meng
   Luboslav Špilák
   Luca Vallisa
   Lukas Fittl
   Maciek Sakrejda
   Magnus Hagander
   Mahendra Singh Thalor
   Mahendrakar Srinivasarao
   Maiquel Grassi
   Maksim Korotkov
   Maksim Melnikov
   Man Zeng
   Marat Buharov
   Marc Balmer
   Marco Nenciarini
   Marcos Pegoraro
   Marina Polyakova
   Mark Callaghan
   Mark Dilger
   Marlene Brandstaetter
   Marlene Reiterer
   Martin Rakhmanov
   Masahiko Sawada
   Masahiro Ikeda
   Masao Fujii
   Mason Mackaman
   Mat Arye
   Matheus Alcantara
   Mats Kindahl
   Matthew Gabeler-Lee
   Matthew Kim
   Matthew Sterrett
   Matthew Woodcraft
   Matthias van de Meent
   Matthieu Denais
   Maurizio Boriani
   Max Johnson
   Max Madden
   Maxim Boguk
   Maxim Orlov
   Maximilian Chrzan
   Melanie Plageman
   Melih Mutlu
   Mert Alev
   Michael Banck
   Michael Bondarenko
   Michael Christofides
   Michael Guissine
   Michael Harris
   Michaël Paquier
   Michail Nikolaev
   Michal Kleczek
   Michel Pelletier
   Mikaël Gourlaouen
   Mikhail Gribkov
   Mikhail Kot
   Milosz Chmura
   Muralikrishna Bandaru
   Murat Efendioglu
   Mutaamba Maasha
   Naeem Akhter
   Nat Makarevitch
   Nathan Bossart
   Navneet Kumar
   Nazir Bilal Yavuz
   Neil Conway
   Niccolò Fei
   Nick Davies
   Nicolas Maus
   Niek Brasa
   Nikhil Raj
   Nikita
   Nikita Kalinin
   Nikita Malakhov
   Nikolay Samokhvalov
   Nikolay Shaplov
   Nisha Moond
   Nitin Jadhav
   Nitin Motiani
   Noah Misch
   Noboru Saito
   Noriyoshi Shinoda
   Ole Peder Brandtzæg
   Oleg Sibiryakov
   Oleg Tselebrovskiy
   Olleg Samoylov
   Onder Kalaci
   Ondrej Navratil
   Patrick Stählin
   Paul Amonson
   Paul Jungwirth
   Paul Ramsey
   Pavel Borisov
   Pavel Luzanov
   Pavel Nekrasov
   Pavel Stehule
   Peter Eisentraut
   Peter Geoghegan
   Peter Mittere
   Peter Smith
   Phil Eaton
   Philipp Salvisberg
   Philippe Beaudoin
   Pierre Giraud
   Pixian Shi
   Polina Bungina
   Przemyslaw Sztoch
   Quynh Tran
   Rafia Sabih
   Raghuveer Devulapalli
   Rahila Syed
   Rama Malladi
   Ran Benita
   Ranier Vilela
   Renan Alves Fonseca
   Richard Guo
   Richard Neill
   Rintaro Ikeda
   Robert Haas
   Robert Treat
   Robins Tharakan
   Roman Zharkov
   Ronald Cruz
   Ronan Dunklau
   Rui Zhao
   Rushabh Lathia
   Rustam Allakov
   Ryo Kanbayashi
   Ryohei Takahashi
   RyotaK
   Sagar Dilip Shedge
   Salvatore Dipietro
   Sam Gabrielsson
   Sam James
   Sameer Kumar
   Sami Imseih
   Samuel Thibault
   Satyanarayana Narlapuram
   Sebastian Skalacki
   Senglee Choi
   Sergei Kornilov
   Sergey Belyashov
   Sergey Dudoladov
   Sergey Prokhorenko
   Sergey Sargsyan
   Sergey Soloviev
   Sergey Tatarintsev
   Shaik Mohammad Mujeeb
   Shawn McCoy
   Shenhao Wang
   Shihao Zhong
   Shinya Kato
   Shlok Kyal
   Shubham Khanna
   Shveta Malik
   Simon Riggs
   Smolkin Grigory
   Sofia Kopikova
   Song Hongyu
   Song Jinzhou
   Soumyadeep Chakraborty
   Sravan Kumar
   Srinath Reddy
   Stan Hu
   Stepan Neretin
   Stephen Fewer
   Stephen Frost
   Steve Chavez
   Steven Niu
   Suraj Kharage
   Sven Klemm
   Takamichi Osumi
   Takeshi Ideriha
   Tatsuo Ishii
   Ted Yu
   Tels
   Tender Wang
   Teodor Sigaev
   Thom Brown
   Thomas Baehler
   Thomas Krennwallner
   Thomas Munro
   Tim Wood
   Timur Magomedov
   Tobias Wendorff
   Todd Cook
   Tofig Aliev
   Tom Lane
   Tomas Vondra
   Tomasz Rybak
   Tomasz Szypowski
   Torsten Foertsch
   Toshi Harada
   Tristan Partin
   Triveni N
   Umar Hayat
   Vallimaharajan G
   Vasya Boytsov
   Victor Yegorov
   Vignesh C
   Viktor Holmberg
   Vinícius Abrahão
   Vinod Sridharan
   Virender Singla
   Vitaly Davydov
   Vladlen Popolitov
   Vladyslav Nebozhyn
   Walid Ibrahim
   Webbo Han
   Wenhui Qiu
   Will Mortensen
   Will Storey
   Wolfgang Walther
   Xin Zhang
   Xing Guo
   Xuneng Zhou
   Yan Chengpen
   Yang Lei
   Yaroslav Saburov
   Yaroslav Syrytsia
   Yasir Hussain
   Yasuo Honda
   Yogesh Sharma
   Yonghao Lee
   Yoran Heling
   Yu Liang
   Yugo Nagata
   Yuhang Qiu
   Yuki Seino
   Yura Sokolov
   Yurii Rashkovskii
   Yushi Ogiwara
   Yusuke Sugie
   Yuta Katsuragi
   Yuto Sasaki
   Yuuki Fujii
   Yuya Watari
   Zane Duffield
   Zeyuan Hu
   Zhang Mingli
   Zhihong Yu
   Zhijie Hou
   Zsolt Parragi