> For the complete documentation index, see [llms.txt](https://docs.postgresql.tw/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.postgresql.tw/appendixes/release/release-18.md).

# E.6. Release 18 \#

[E.6.1. Overview](#RELEASE-18-HIGHLIGHTS)

[E.6.2. Migration to Version 18](#RELEASE-18-MIGRATION)

[E.6.3. Changes](#RELEASE-18-CHANGES)

[E.6.4. Acknowledgments](#RELEASE-18-ACKNOWLEDGEMENTS)

\*\*Release date:\*\*2025-09-25

## E.6.1. Overview [#](#RELEASE-18-HIGHLIGHTS)

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](/reference/reference-server/pgupgrade.md) now retains optimizer statistics.
* Support for "skip scan" lookups that allow using [multicolumn B-tree indexes](/the-sql-language/indexes/indexes-multicolumn.md) in more cases.
* [`uuidv7()`](/the-sql-language/functions/functions-uuid.md#FUNC_UUID_GEN_TABLE) function for generating timestamp-ordered [UUIDs](/the-sql-language/datatype/datatype-uuid.md).
* Virtual [generated columns](/reference/sql-commands/sql-createtable.md#SQL-CREATETABLE-PARMS-GENERATED-STORED) that compute their values during read operations. This is now the default for generated columns.
* [OAuth authentication](/server-administration/client-authentication/auth-oauth.md) support.
* `OLD` and `NEW` support for [`RETURNING`](/the-sql-language/dml/dml-returning.md) clauses in [INSERT](/reference/sql-commands/sql-insert.md), [UPDATE](/reference/sql-commands/sql-update.md), [DELETE](/reference/sql-commands/sql-delete.md), and [MERGE](/reference/sql-commands/sql-merge.md) commands.
* Temporal constraints, or constraints over ranges, for [PRIMARY KEY](/reference/sql-commands/sql-createtable.md#SQL-CREATETABLE-PARMS-PRIMARY-KEY), [UNIQUE](/reference/sql-commands/sql-createtable.md#SQL-CREATETABLE-PARMS-UNIQUE), and [FOREIGN KEY](/reference/sql-commands/sql-createtable.md#SQL-CREATETABLE-PARMS-REFERENCES) constraints.

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

## E.6.2. Migration to Version 18 [#](#RELEASE-18-MIGRATION)

A dump/restore using [pg\_dumpall](/reference/reference-client/app-pg-dumpall.md) or use of [pg\_upgrade](/reference/reference-server/pgupgrade.md) or logical replication is required for those wishing to migrate data from any previous release. See [Section 18.6](/server-administration/runtime/upgrading.md) 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](/reference/reference-server/app-initdb.md) default to enable data checksums (Greg Sabino Mullane) [§](https://postgr.es/c/04bec894a04)

  Checksums can be disabled with the new initdb option `--no-data-checksums`. [pg\_upgrade](/reference/reference-server/pgupgrade.md) 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) [§](https://postgr.es/c/d7674c9fa)

  The system will now favor the current session's time zone abbreviations before checking the server variable [timezone\_abbreviations](/server-administration/runtime-config/runtime-config-client.md#GUC-TIMEZONE-ABBREVIATIONS). Previously `timezone_abbreviations` was checked first.
* Deprecate [MD5 password](/server-administration/client-authentication/auth-password.md) authentication (Nathan Bossart) [§](https://postgr.es/c/db6a4a985)

  Support for MD5 passwords will be removed in a future major version release. [CREATE ROLE](/reference/sql-commands/sql-createrole.md) and [ALTER ROLE](/reference/sql-commands/sql-alterrole.md) now emit deprecation warnings when setting MD5 passwords. These warnings can be disabled by setting the [md5\_password\_warnings](/server-administration/runtime-config/runtime-config-connection.md#GUC-MD5-PASSWORD-WARNINGS) parameter to `off`.
* Change [VACUUM](/reference/sql-commands/sql-vacuum.md) and [ANALYZE](/reference/sql-commands/sql-analyze.md) to process the inheritance children of a parent (Michael Harris) [§](https://postgr.es/c/62ddf7ee9)

  The previous behavior can be performed by using the new `ONLY` option.
* Prevent [`COPY FROM`](/reference/sql-commands/sql-copy.md) from treating `\.` as an end-of-file marker when reading CSV files (Daniel Vérité, Tom Lane) [§](https://postgr.es/c/770233748) [§](https://postgr.es/c/da8a4c166)

  [psql](/reference/reference-client/app-psql.md) 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`](/reference/reference-client/app-psql.md#APP-PSQL-META-COMMANDS-COPY) problems. This release also enforces that `\.` must appear alone on a line.
* Disallow unlogged partitioned tables (Michael Paquier) [§](https://postgr.es/c/e2bab2d79)

  Previously [`ALTER TABLE SET [UN]LOGGED`](/reference/sql-commands/sql-altertable.md) did nothing, and the creation of an unlogged partitioned table did not cause its children to be unlogged.
* Execute `AFTER` [triggers](/server-programming/triggers.md) as the role that was active when trigger events were queued (Laurenz Albe) [§](https://postgr.es/c/01463e1cc)

  Previously such triggers were run as the role that was active at trigger execution time (e.g., at [COMMIT](/reference/sql-commands/sql-commit.md)). 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](/reference/sql-commands/sql-grant.md)/[REVOKE](/reference/sql-commands/sql-revoke.md) (Fujii Masao) [§](https://postgr.es/c/fefa76f70)

  These have been non-functional since PostgreSQL 8.2.
* Remove column [`pg_backend_memory_contexts`](/internals/views/view-pg-backend-memory-contexts.md).`parent` (Melih Mutlu) [§](https://postgr.es/c/f0d112759)

  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()`](/the-sql-language/functions/functions-admin.md#FUNCTIONS-ADMIN-SIGNAL-TABLE) to be one-based (Melih Mutlu, Atsushi Torikoshi, David Rowley, Fujii Masao) [§](https://postgr.es/c/32d3ed816) [§](https://postgr.es/c/d9e03864b) [§](https://postgr.es/c/706cbed35)

  These were previously zero-based.
* Change [full text search](/the-sql-language/textsearch.md) to use the default collation provider of the cluster to read configuration files and dictionaries, rather than always using libc (Peter Eisentraut) [§](https://postgr.es/c/fb1a18810f0)

  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](/appendixes/contrib/pgtrgm.md) extension. When upgrading such clusters using [pg\_upgrade](/reference/reference-server/pgupgrade.md), it is recommended to reindex all indexes related to full-text search and pg\_trgm after the upgrade.

## E.6.3. Changes [#](#RELEASE-18-CHANGES)

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

### E.6.3.1. Server [#](#RELEASE-18-SERVER)

#### E.6.3.1.1. Optimizer [#](#RELEASE-18-OPTIMIZER)

* Automatically remove some unnecessary table self-joins (Andrey Lepikhov, Alexander Kuzmenkov, Alexander Korotkov, Alena Rybakina) [§](https://postgr.es/c/fc069a3a6)

  This optimization can be disabled using server variable [enable\_self\_join\_elimination](/server-administration/runtime-config/runtime-config-query.md#GUC-ENABLE-SELF-JOIN-ELIMINATION).
* Convert some [`IN (VALUES ...)`](/the-sql-language/functions/functions-comparisons.md#FUNCTIONS-COMPARISONS-IN-SCALAR) to `x = ANY ...` for better optimizer statistics (Alena Rybakina, Andrei Lepikhov) [§](https://postgr.es/c/c0962a113)
* Allow transforming [`OR`](/the-sql-language/functions/functions-logical.md)-clauses to arrays for faster index processing (Alexander Korotkov, Andrey Lepikhov) [§](https://postgr.es/c/ae4569161)
* Speed up the processing of [`INTERSECT`](/reference/sql-commands/sql-select.md#SQL-INTERSECT), [`EXCEPT`](/reference/sql-commands/sql-select.md#SQL-EXCEPT), [window aggregates](/tutorial/tutorial-advanced/tutorial-window.md), and [view column aliases](/reference/sql-commands/sql-createview.md) (Tom Lane, David Rowley) [§](https://postgr.es/c/52c707483) [§](https://postgr.es/c/276279295) [§](https://postgr.es/c/8d96f57d5) [§](https://postgr.es/c/908a96861)
* Allow the keys of [`SELECT DISTINCT`](/reference/sql-commands/sql-select.md#SQL-DISTINCT) to be internally reordered to avoid sorting (Richard Guo) [§](https://postgr.es/c/a8ccf4e93)

  This optimization can be disabled using [enable\_distinct\_reordering](/server-administration/runtime-config/runtime-config-query.md#GUC-ENABLE-DISTINCT-REORDERING).
* Ignore [`GROUP BY`](/reference/sql-commands/sql-select.md#SQL-GROUPBY) columns that are functionally dependent on other columns (Zhang Mingli, Jian He, David Rowley) [§](https://postgr.es/c/bd10ec529)

  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`](/reference/sql-commands/sql-select.md#SQL-HAVING) clauses on [`GROUPING SETS`](/the-sql-language/queries/queries-table-expressions.md#QUERIES-GROUPING-SETS) to be pushed to [`WHERE`](/reference/sql-commands/sql-select.md#SQL-WHERE) clauses (Richard Guo) [§](https://postgr.es/c/67a54b9e8) [§](https://postgr.es/c/247dea89f) [§](https://postgr.es/c/f5050f795) [§](https://postgr.es/c/cc5d98525)

  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()`](/the-sql-language/functions/functions-srf.md#FUNCTIONS-SRF-SERIES) using [`numeric`](/the-sql-language/datatype/datatype-numeric.md) and [`timestamp`](/the-sql-language/datatype/datatype-datetime.md) values (David Rowley, Song Jinzhou) [§](https://postgr.es/c/036bdcec9) [§](https://postgr.es/c/97173536e)
* Allow the optimizer to use `Right Semi Join` plans (Richard Guo) [§](https://postgr.es/c/aa86129e1)

  Semi-joins are used when needing to find if there is at least one match.
* Allow merge joins to use [incremental sorts](/server-administration/runtime-config/runtime-config-query.md#GUC-ENABLE-INCREMENTAL-SORT) (Richard Guo) [§](https://postgr.es/c/828e94c9d)
* Improve the efficiency of planning queries accessing many partitions (Ashutosh Bapat, Yuya Watari, David Rowley) [§](https://postgr.es/c/88f55bc97) [§](https://postgr.es/c/d69d45a5a)
* Allow [partitionwise joins](/server-administration/runtime-config/runtime-config-query.md#GUC-ENABLE-PARTITIONWISE-JOIN) in more cases, and reduce its memory usage (Richard Guo, Tom Lane, Ashutosh Bapat) [§](https://postgr.es/c/9b282a935) [§](https://postgr.es/c/513f4472a)
* Improve cost estimates of partition queries (Nikita Malakhov, Andrei Lepikhov) [§](https://postgr.es/c/fae535da0)
* Improve [SQL-language function](/server-programming/extend/xfunc-sql.md) plan caching (Alexander Pyhalov, Tom Lane) [§](https://postgr.es/c/0dca5d68d) [§](https://postgr.es/c/09b07c295)
* Improve handling of disabled optimizer features (Robert Haas) [§](https://postgr.es/c/e22253467)

#### E.6.3.1.2. Indexes [#](#RELEASE-18-INDEXES)

* Allow skip scans of [btree](/server-programming/extend/xfunc-sql.md) indexes (Peter Geoghegan) [§](https://postgr.es/c/92fe23d93) [§](https://postgr.es/c/8a510275d)

  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) [§](https://postgr.es/c/f278e1fe3) [§](https://postgr.es/c/9d6db8bec)

  The index type must still support equality.
* Allow [`GIN`](/internals/indextypes/gin.md) indexes to be created in parallel (Tomas Vondra, Matthias van de Meent) [§](https://postgr.es/c/8492feb98)
* Allow values to be sorted to speed range-type [GiST](/internals/indextypes/gist.md) and [btree](/internals/indextypes/btree.md) index builds (Bernd Helmle) [§](https://postgr.es/c/e9e7b6604)

#### E.6.3.1.3. General Performance [#](#RELEASE-18-PERFORMANCE)

* Add an asynchronous I/O subsystem (Andres Freund, Thomas Munro, Nazir Bilal Yavuz, Melanie Plageman) [§](https://postgr.es/c/02844012b) [§](https://postgr.es/c/da7226993) [§](https://postgr.es/c/55b454d0e) [§](https://postgr.es/c/247ce06b8) [§](https://postgr.es/c/10f664684) [§](https://postgr.es/c/06fb5612c) [§](https://postgr.es/c/c325a7633) [§](https://postgr.es/c/50cb7505b) [§](https://postgr.es/c/047cba7fa) [§](https://postgr.es/c/12ce89fd0) [§](https://postgr.es/c/2a5e709e7)

  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](/server-administration/runtime-config/runtime-config-resource.md#GUC-IO-METHOD), with server variables [io\_combine\_limit](/server-administration/runtime-config/runtime-config-resource.md#GUC-IO-COMBINE-LIMIT) and [io\_max\_combine\_limit](/server-administration/runtime-config/runtime-config-resource.md#GUC-IO-MAX-COMBINE-LIMIT) added to control it. This also enables [effective\_io\_concurrency](/server-administration/runtime-config/runtime-config-resource.md#GUC-EFFECTIVE-IO-CONCURRENCY) and [maintenance\_io\_concurrency](/server-administration/runtime-config/runtime-config-resource.md#GUC-MAINTENANCE-IO-CONCURRENCY) values greater than zero for systems without `fadvise()` support. The new system view [`pg_aios`](/internals/views/view-pg-aios.md) shows the file handles being used for asynchronous I/O.
* Improve the locking performance of queries that access many relations (Tomas Vondra) [§](https://postgr.es/c/c4d5cb71d)
* Improve the performance and reduce memory usage of hash joins and [`GROUP BY`](/reference/sql-commands/sql-select.md#SQL-GROUPBY) (David Rowley, Jeff Davis) [§](https://postgr.es/c/adf97c156) [§](https://postgr.es/c/0f5738202) [§](https://postgr.es/c/4d143509c) [§](https://postgr.es/c/a0942f441) [§](https://postgr.es/c/626df47ad)

  This also improves hash set operations used by [`EXCEPT`](/reference/sql-commands/sql-select.md#SQL-EXCEPT), and hash lookups of subplan values.
* Allow normal vacuums to freeze some pages, even though they are all-visible (Melanie Plageman) [§](https://postgr.es/c/052026c9b) [§](https://postgr.es/c/06eae9e62)

  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](/server-administration/runtime-config/runtime-config-vacuum.md#GUC-VACUUM-MAX-EAGER-FREEZE-FAILURE-RATE). Previously vacuum never processed all-visible pages until freezing was required.
* Add server variable [vacuum\_truncate](/server-administration/runtime-config/runtime-config-vacuum.md#GUC-VACUUM-TRUNCATE) to control file truncation during [VACUUM](/reference/sql-commands/sql-vacuum.md) (Nathan Bossart, Gurjeet Singh) [§](https://postgr.es/c/0164a0f9e)

  A storage-level parameter with the same name and behavior already existed.
* Increase server variables [effective\_io\_concurrency](/server-administration/runtime-config/runtime-config-resource.md#GUC-EFFECTIVE-IO-CONCURRENCY)'s and [maintenance\_io\_concurrency](/server-administration/runtime-config/runtime-config-resource.md#GUC-MAINTENANCE-IO-CONCURRENCY)'s default values to 16 (Melanie Plageman) [§](https://postgr.es/c/ff79b5b2a) [§](https://postgr.es/c/cc6be07eb)

  This more accurately reflects modern hardware.

#### E.6.3.1.4. Monitoring [#](#RELEASE-18-MONITORING)

* Increase the logging granularity of server variable [log\_connections](/server-administration/runtime-config/runtime-config-logging.md#GUC-LOG-CONNECTIONS) (Melanie Plageman) [§](https://postgr.es/c/9219093ca)

  This server variable was previously only boolean, which is still supported.
* Add `log_connections` option to report the duration of connection stages (Melanie Plageman) [§](https://postgr.es/c/18cd15e70)
* Add [log\_line\_prefix](/server-administration/runtime-config/runtime-config-logging.md#GUC-LOG-LINE-PREFIX) escape `%L` to output the client IP address (Greg Sabino Mullane) [§](https://postgr.es/c/3516ea768)
* Add server variable [log\_lock\_failures](/server-administration/runtime-config/runtime-config-logging.md#GUC-LOG-LOCK-FAILURES) to log lock acquisition failures (Yuki Seino, Fujii Masao) [§](https://postgr.es/c/6d376c3b0) [§](https://postgr.es/c/73bdcfab3)

  Specifically it reports [`SELECT ... NOWAIT`](/reference/sql-commands/sql-select.md#SQL-FOR-UPDATE-SHARE) lock failures.
* Modify [`pg_stat_all_tables`](/server-administration/monitoring/monitoring-stats.md#MONITORING-PG-STAT-ALL-TABLES-VIEW) and its variants to report the time spent in [VACUUM](/reference/sql-commands/sql-vacuum.md), [ANALYZE](/reference/sql-commands/sql-analyze.md), and their [automatic](/server-administration/maintenance/routine-vacuuming.md#AUTOVACUUM) variants (Sami Imseih) [§](https://postgr.es/c/30a6ed0ce)

  The new columns are `total_vacuum_time`, `total_autovacuum_time`, `total_analyze_time`, and `total_autoanalyze_time`.
* Add delay time reporting to [VACUUM](/reference/sql-commands/sql-vacuum.md) and [ANALYZE](/reference/sql-commands/sql-analyze.md) (Bertrand Drouvot, Nathan Bossart) [§](https://postgr.es/c/bb8dff999) [§](https://postgr.es/c/7720082ae)

  This information appears in the server log, the system views [`pg_stat_progress_vacuum`](/server-administration/monitoring/progress-reporting.md#VACUUM-PROGRESS-REPORTING) and [`pg_stat_progress_analyze`](/server-administration/monitoring/progress-reporting.md#PG-STAT-PROGRESS-ANALYZE-VIEW), and the output of [VACUUM](/reference/sql-commands/sql-vacuum.md) and [ANALYZE](/reference/sql-commands/sql-analyze.md) when in `VERBOSE` mode; tracking must be enabled with the server variable [track\_cost\_delay\_timing](/server-administration/runtime-config/runtime-config-statistics.md#GUC-TRACK-COST-DELAY-TIMING).
* Add WAL, CPU, and average read statistics output to `ANALYZE VERBOSE` (Anthonin Bonnefoy) [§](https://postgr.es/c/4c1b4cdb8) [§](https://postgr.es/c/bb7775234)
* Add full WAL buffer count to `VACUUM`/`ANALYZE (VERBOSE)` and autovacuum log output (Bertrand Drouvot) [§](https://postgr.es/c/6a8a7ce47)
* Add per-backend I/O statistics reporting (Bertrand Drouvot) [§](https://postgr.es/c/9aea73fc6) [§](https://postgr.es/c/3f1db99bf)

  The statistics are accessed via [`pg_stat_get_backend_io()`](/server-administration/monitoring/monitoring-stats.md#PG-STAT-GET-BACKEND-IO). Per-backend I/O statistics can be cleared via [`pg_stat_reset_backend_stats()`](/server-administration/monitoring/monitoring-stats.md#MONITORING-STATS-FUNCS-TABLE).
* Add [`pg_stat_io`](/server-administration/monitoring/monitoring-stats.md#MONITORING-PG-STAT-IO-VIEW) columns to report I/O activity in bytes (Nazir Bilal Yavuz) [§](https://postgr.es/c/f92c854cf)

  The new columns are `read_bytes`, `write_bytes`, and `extend_bytes`. The `op_bytes` column, which always equaled [`BLCKSZ`](/server-administration/runtime-config/runtime-config-preset.md#GUC-BLOCK-SIZE), has been removed.
* Add WAL I/O activity rows to `pg_stat_io` (Nazir Bilal Yavuz, Bertrand Drouvot, Michael Paquier) [§](https://postgr.es/c/a051e71e2) [§](https://postgr.es/c/4538bd3f1) [§](https://postgr.es/c/7f7f324eb)

  This includes WAL receiver activity and a wait event for such writes.
* Change server variable [track\_wal\_io\_timing](/server-administration/runtime-config/runtime-config-statistics.md#GUC-TRACK-WAL-IO-TIMING) to control tracking WAL timing in `pg_stat_io` instead of [`pg_stat_wal`](/server-administration/monitoring/monitoring-stats.md#PG-STAT-WAL-VIEW) (Bertrand Drouvot) [§](https://postgr.es/c/6c349d83b)
* Remove read/sync columns from `pg_stat_wal` (Bertrand Drouvot) [§](https://postgr.es/c/2421e9a51) [§](https://postgr.es/c/6c349d83b)

  This removes columns `wal_write`, `wal_sync`, `wal_write_time`, and `wal_sync_time`.
* Add function [`pg_stat_get_backend_wal()`](/server-administration/monitoring/monitoring-stats.md#PG-STAT-GET-BACKEND-WAL) to return per-backend WAL statistics (Bertrand Drouvot) [§](https://postgr.es/c/76def4cdd)

  Per-backend WAL statistics can be cleared via [`pg_stat_reset_backend_stats()`](/server-administration/monitoring/monitoring-stats.md#MONITORING-STATS-FUNCS-TABLE).
* Add function [`pg_ls_summariesdir()`](/the-sql-language/functions/functions-admin.md#FUNCTIONS-ADMIN-GENFILE-TABLE) to specifically list the contents of [`PGDATA`](/internals/storage/storage-file-layout.md)/[`pg_wal/summaries`](/server-administration/runtime-config/runtime-config-wal.md#GUC-WAL-SUMMARY-KEEP-TIME) (Yushi Ogiwara) [§](https://postgr.es/c/4e1fad378)
* Add column [`pg_stat_checkpointer`](/server-administration/monitoring/monitoring-stats.md#MONITORING-PG-STAT-CHECKPOINTER-VIEW).`num_done` to report the number of completed checkpoints (Anton A. Melnikov) [§](https://postgr.es/c/559efce1d)

  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) [§](https://postgr.es/c/17cc5f666)

  Also, modify the checkpoint server log message to report separate shared buffer and SLRU buffer values.
* Add columns to [`pg_stat_database`](/server-administration/monitoring/monitoring-stats.md#MONITORING-PG-STAT-DATABASE-VIEW) to report parallel worker activity (Benoit Lobréau) [§](https://postgr.es/c/e7a9496de)

  The new columns are `parallel_workers_to_launch` and `parallel_workers_launched`.
* Have [query id](/server-administration/runtime-config/runtime-config-statistics.md#GUC-COMPUTE-QUERY-ID) computation of constant lists consider only the first and last constants (Dmitry Dolgov, Sami Imseih) [§](https://postgr.es/c/62d712ecf) [§](https://postgr.es/c/9fbd53dea) [§](https://postgr.es/c/c2da1a5d6)

  Jumbling is used by [pg\_stat\_statements](/appendixes/contrib/pgstatstatements.md).
* Adjust query id computations to group together queries using the same relation name (Michael Paquier, Sami Imseih) [§](https://postgr.es/c/787514b30)

  This is true even if the tables in different schemas have different column names.
* Add column [`pg_backend_memory_contexts`](/internals/views/view-pg-backend-memory-contexts.md).`type` to report the type of memory context (David Rowley) [§](https://postgr.es/c/12227a1d5)
* Add column `pg_backend_memory_contexts`.`path` to show memory context parents (Melih Mutlu) [§](https://postgr.es/c/32d3ed816)

#### E.6.3.1.5. Privileges [#](#RELEASE-18-PRIVILEGES)

* Add function [`pg_get_acl()`](/the-sql-language/functions/functions-info.md#FUNCTIONS-INFO-OBJECT-TABLE) to retrieve database access control details (Joel Jacobson) [§](https://postgr.es/c/4564f1ceb) [§](https://postgr.es/c/d898665bf)
* Add function [`has_largeobject_privilege()`](/the-sql-language/functions/functions-info.md#FUNCTIONS-INFO-ACCESS-TABLE) to check large object privileges (Yugo Nagata) [§](https://postgr.es/c/4eada203a)
* Allow [ALTER DEFAULT PRIVILEGES](/reference/sql-commands/sql-alterdefaultprivileges.md) to define large object default privileges (Takatsuka Haruka, Yugo Nagata, Laurenz Albe) [§](https://postgr.es/c/0d6c47766)
* Add predefined role [`pg_signal_autovacuum_worker`](/server-administration/user-manag/predefined-roles.md) (Kirill Reshke) [§](https://postgr.es/c/ccd38024b)

  This allows sending signals to autovacuum workers.

#### E.6.3.1.6. Server Configuration [#](#RELEASE-18-SERVER-CONFIG)

* Add support for the [OAuth authentication method](/server-administration/client-authentication/auth-oauth.md) (Jacob Champion, Daniel Gustafsson, Thomas Munro) [§](https://postgr.es/c/b3f0be788)

  This adds an `oauth` authentication method to [`pg_hba.conf`](/server-administration/client-authentication/auth-pg-hba-conf.md), libpq OAuth options, a server variable [oauth\_validator\_libraries](/server-administration/runtime-config/runtime-config-connection.md#GUC-OAUTH-VALIDATOR-LIBRARIES) to load token validation libraries, and a configure flag [`--with-libcurl`](/server-administration/installation/install-make.md#CONFIGURE-OPTION-WITH-LIBCURL) to add the required compile-time libraries.
* Add server variable [ssl\_tls13\_ciphers](/server-administration/runtime-config/runtime-config-connection.md#GUC-SSL-TLS13-CIPHERS) to allow specification of multiple colon-separated TLSv1.3 cipher suites (Erica Zhang, Daniel Gustafsson) [§](https://postgr.es/c/45188c2ea)
* Change server variable [ssl\_groups](/server-administration/runtime-config/runtime-config-connection.md#GUC-SSL-GROUPS)'s default to include elliptic curve X25519 (Daniel Gustafsson, Jacob Champion) [§](https://postgr.es/c/daa02c6bd)
* Rename server variable `ssl_ecdh_curve` to [ssl\_groups](/server-administration/runtime-config/runtime-config-connection.md#GUC-SSL-GROUPS) and allow multiple colon-separated ECDH curves to be specified (Erica Zhang, Daniel Gustafsson) [§](https://postgr.es/c/3d1ef3a15)

  The previous name still works.
* Make [cancel request keys](/the-sql-language/functions/functions-admin.md#FUNCTIONS-ADMIN-SIGNAL-TABLE) 256 bits (Heikki Linnakangas, Jelte Fennema-Nio) [§](https://postgr.es/c/a460251f0) [§](https://postgr.es/c/9d9b9d46f)

  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](/server-administration/runtime-config/runtime-config-vacuum.md#GUC-AUTOVACUUM-WORKER-SLOTS) to specify the maximum number of background workers (Nathan Bossart) [§](https://postgr.es/c/c758119e5)

  With this variable set, [autovacuum\_max\_workers](/server-administration/runtime-config/runtime-config-vacuum.md#GUC-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](/server-administration/maintenance/routine-vacuuming.md#AUTOVACUUM) (Nathan Bossart, Frédéric Yhuel) [§](https://postgr.es/c/306dc520b)

  The server variable is [autovacuum\_vacuum\_max\_threshold](/server-administration/runtime-config/runtime-config-vacuum.md#GUC-AUTOVACUUM-VACUUM-MAX-THRESHOLD). Percentages are still used for triggering.
* Change server variable [max\_files\_per\_process](/server-administration/runtime-config/runtime-config-resource.md#GUC-MAX-FILES-PER-PROCESS) to limit only files opened by a backend (Andres Freund) [§](https://postgr.es/c/adb5f85fa)

  Previously files opened by the postmaster were also counted toward this limit.
* Add server variable [num\_os\_semaphores](/server-administration/runtime-config/runtime-config-preset.md#GUC-NUM-OS-SEMAPHORES) to report the required number of semaphores (Nathan Bossart) [§](https://postgr.es/c/0dcaea569)

  This is useful for operating system configuration.
* Add server variable [extension\_control\_path](/server-administration/runtime-config/runtime-config-client.md#GUC-EXTENSION-CONTROL-PATH) to specify the location of extension control files (Peter Eisentraut, Matheus Alcantara) [§](https://postgr.es/c/4f7f7b037) [§](https://postgr.es/c/81eaaa2c4)

#### E.6.3.1.7. Streaming Replication and Recovery [#](#RELEASE-18-REPLICATION)

* Allow inactive replication slots to be automatically invalidated using server variable [idle\_replication\_slot\_timeout](/server-administration/runtime-config/runtime-config-replication.md#GUC-IDLE-REPLICATION-SLOT-TIMEOUT) (Nisha Moond, Bharath Rupireddy) [§](https://postgr.es/c/ac0e33136)
* Add server variable [max\_active\_replication\_origins](/server-administration/runtime-config/runtime-config-replication.md#GUC-MAX-ACTIVE-REPLICATION-ORIGINS) to control the maximum active replication origins (Euler Taveira) [§](https://postgr.es/c/04ff636cb)

  This was previously controlled by [max\_replication\_slots](/server-administration/runtime-config/runtime-config-replication.md#GUC-MAX-REPLICATION-SLOTS), but this new setting allows a higher origin count in cases where fewer slots are required.

#### E.6.3.1.8. [Logical Replication](/server-administration/logical-replication.md) [#](#RELEASE-18-LOGICAL)

* Allow the values of [generated columns](/reference/sql-commands/sql-createtable.md#SQL-CREATETABLE-PARMS-GENERATED-STORED) to be logically replicated (Shubham Khanna, Vignesh C, Zhijie Hou, Shlok Kyal, Peter Smith) [§](https://postgr.es/c/745217a05) [§](https://postgr.es/c/7054186c4) [§](https://postgr.es/c/87ce27de6) [§](https://postgr.es/c/6252b1eaf)

  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](/reference/sql-commands/sql-createsubscription.md) streaming option from `off` to `parallel` (Vignesh C) [§](https://postgr.es/c/1bf1140be)
* Allow [ALTER SUBSCRIPTION](/reference/sql-commands/sql-altersubscription.md) to change the replication slot's two-phase commit behavior (Hayato Kuroda, Ajin Cherian, Amit Kapila, Zhijie Hou) [§](https://postgr.es/c/1462aad2e) [§](https://postgr.es/c/4868c96bc)
* Log [conflicts](/server-administration/high-availability/hot-standby.md#HOT-STANDBY-CONFLICT) while applying logical replication changes (Zhijie Hou, Nisha Moond) [§](https://postgr.es/c/9758174e2) [§](https://postgr.es/c/edcb71258) [§](https://postgr.es/c/640178c92) [§](https://postgr.es/c/6c2b5edec) [§](https://postgr.es/c/73eba5004)

  Also report in new columns of [`pg_stat_subscription_stats`](/server-administration/monitoring/monitoring-stats.md#MONITORING-PG-STAT-SUBSCRIPTION-STATS).

### E.6.3.2. Utility Commands [#](#RELEASE-18-UTILITY)

* Allow [generated columns](/reference/sql-commands/sql-createtable.md#SQL-CREATETABLE-PARMS-GENERATED-STORED) to be virtual, and make them the default (Peter Eisentraut, Jian He, Richard Guo, Dean Rasheed) [§](https://postgr.es/c/83ea6c540) [§](https://postgr.es/c/cdc168ad4) [§](https://postgr.es/c/1e4351af3)

  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`](/the-sql-language/dml/dml-returning.md) in DML queries (Dean Rasheed) [§](https://postgr.es/c/80feb727c)

  Previously `RETURNING` only returned new values for [INSERT](/reference/sql-commands/sql-insert.md) and [UPDATE](/reference/sql-commands/sql-update.md), and old values for [DELETE](/reference/sql-commands/sql-delete.md); [MERGE](/reference/sql-commands/sql-merge.md) 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) [§](https://postgr.es/c/302cf1575)

  The syntax is [`CREATE FOREIGN TABLE ... LIKE`](/reference/sql-commands/sql-createforeigntable.md).
* Allow [`LIKE`](/the-sql-language/functions/functions-matching.md#FUNCTIONS-LIKE) with [nondeterministic collations](/server-administration/charset/collation.md#COLLATION-NONDETERMINISTIC) (Peter Eisentraut) [§](https://postgr.es/c/85b7efa1c)
* Allow text position search functions with nondeterministic collations (Peter Eisentraut) [§](https://postgr.es/c/329304c90)

  These used to generate an error.
* Add builtin collation provider [`PG_UNICODE_FAST`](/server-administration/charset/locale.md#LOCALE-PROVIDERS) (Jeff Davis) [§](https://postgr.es/c/d3d098316)

  This locale supports case mapping, but sorts in code point order, not natural language order.
* Allow [VACUUM](/reference/sql-commands/sql-vacuum.md) and [ANALYZE](/reference/sql-commands/sql-analyze.md) to process partitioned tables without processing their children (Michael Harris) [§](https://postgr.es/c/62ddf7ee9)

  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) [§](https://postgr.es/c/e839c8ecc) [§](https://postgr.es/c/d32d14639) [§](https://postgr.es/c/650ab8aaf)

  The functions are [`pg_restore_relation_stats()`](/the-sql-language/functions/functions-admin.md#FUNCTIONS-ADMIN-STATSMOD), `pg_restore_attribute_stats()`, `pg_clear_relation_stats()`, and `pg_clear_attribute_stats()`.
* Add server variable [file\_copy\_method](/server-administration/runtime-config/runtime-config-resource.md#GUC-FILE-COPY-METHOD) to control the file copying method (Nazir Bilal Yavuz) [§](https://postgr.es/c/f78ca6f3e)

  This controls whether [`CREATE DATABASE ... STRATEGY=FILE_COPY`](/reference/sql-commands/sql-createdatabase.md) and [`ALTER DATABASE ... SET TABLESPACE`](/reference/sql-commands/sql-alterdatabase.md) uses file copy or clone.

#### E.6.3.2.1. [Constraints](/the-sql-language/ddl/ddl-constraints.md) [#](#RELEASE-18-CONSTRAINTS)

* Allow the specification of non-overlapping [`PRIMARY KEY`](/reference/sql-commands/sql-createtable.md#SQL-CREATETABLE-PARMS-PRIMARY-KEY), [`UNIQUE`](/reference/sql-commands/sql-createtable.md#SQL-CREATETABLE-PARMS-UNIQUE), and [foreign key](/reference/sql-commands/sql-createtable.md#SQL-CREATETABLE-PARMS-REFERENCES) constraints (Paul A. Jungwirth) [§](https://postgr.es/c/fc0438b4e) [§](https://postgr.es/c/89f908a6d)

  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`](/reference/sql-commands/sql-createtable.md#SQL-CREATETABLE-PARMS-CHECK) and [foreign key](/reference/sql-commands/sql-createtable.md#SQL-CREATETABLE-PARMS-REFERENCES) constraints to be specified as `NOT ENFORCED` (Amul Sul) [§](https://postgr.es/c/ca87c415e) [§](https://postgr.es/c/eec0040c4)

  This also adds column [`pg_constraint`](/internals/catalogs/catalog-pg-constraint.md).`conenforced`.
* Require [primary/foreign key](/reference/sql-commands/sql-createtable.md#SQL-CREATETABLE-PARMS-REFERENCES) relationships to use either deterministic collations or the the same nondeterministic collations (Peter Eisentraut) [§](https://postgr.es/c/9321d2fdf)

  The restore of a [pg\_dump](/reference/reference-client/app-pgdump.md), also used by [pg\_upgrade](/reference/reference-server/pgupgrade.md), will fail if these requirements are not met; schema changes must be made for these upgrade methods to succeed.
* Store column [`NOT NULL`](/reference/sql-commands/sql-createtable.md#SQL-CREATETABLE-PARMS-NOT-NULL) specifications in [`pg_constraint`](/internals/catalogs/catalog-pg-constraint.md) (Álvaro Herrera, Bernd Helmle) [§](https://postgr.es/c/14e87ffa5) [§](https://postgr.es/c/81ce602d4)

  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](/reference/sql-commands/sql-altertable.md) to set the `NOT VALID` attribute of `NOT NULL` constraints (Rushabh Lathia, Jian He) [§](https://postgr.es/c/a379061a2)
* Allow modification of the inheritability of `NOT NULL` constraints (Suraj Kharage, Álvaro Herrera) [§](https://postgr.es/c/f4e53e10b) [§](https://postgr.es/c/4a02af8b1)

  The syntax is [`ALTER TABLE ... ALTER CONSTRAINT ... [NO] INHERIT`](/reference/sql-commands/sql-altertable.md).
* Allow `NOT VALID` foreign key constraints on partitioned tables (Amul Sul) [§](https://postgr.es/c/b663b9436)
* Allow [dropping](/reference/sql-commands/sql-altertable.md#SQL-ALTERTABLE-DESC-DROP-CONSTRAINT) of constraints `ONLY` on partitioned tables (Álvaro Herrera) [§](https://postgr.es/c/4dea33ce7)

  This was previously erroneously prohibited.

#### E.6.3.2.2. [COPY](/reference/sql-commands/sql-copy.md) [#](#RELEASE-18-COPY)

* Add `REJECT_LIMIT` to control the number of invalid rows `COPY FROM` can ignore (Atsushi Torikoshi) [§](https://postgr.es/c/4ac2a9bec)

  This is available when `ON_ERROR = 'ignore'`.
* Allow `COPY TO` to copy rows from populated materialized views (Jian He) [§](https://postgr.es/c/534874fac)
* Add `COPY` `LOG_VERBOSITY` level `silent` to suppress log output of ignored rows (Atsushi Torikoshi) [§](https://postgr.es/c/e7834a1a2)

  This new level suppresses output for discarded input rows when `on_error = 'ignore'`.
* Disallow `COPY FREEZE` on foreign tables (Nathan Bossart) [§](https://postgr.es/c/401a6956f)

  Previously, the `COPY` worked but the `FREEZE` was ignored, so disallow this command.

#### E.6.3.2.3. [EXPLAIN](/reference/sql-commands/sql-explain.md) [#](#RELEASE-18-EXPLAIN)

* Automatically include `BUFFERS` output in `EXPLAIN ANALYZE` (Guillaume Lelarge, David Rowley) [§](https://postgr.es/c/c2a4078eb)
* Add full WAL buffer count to `EXPLAIN (WAL)` output (Bertrand Drouvot) [§](https://postgr.es/c/320545bfc)
* In `EXPLAIN ANALYZE`, report the number of index lookups used per index scan node (Peter Geoghegan) [§](https://postgr.es/c/0fbceae84)
* Modify `EXPLAIN` to output fractional row counts (Ibrar Ahmed, Ilia Evdokimov, Robert Haas) [§](https://postgr.es/c/ddb17e387) [§](https://postgr.es/c/95dbd827f)
* Add memory and disk usage details to `Material`, `Window Aggregate`, and common table expression nodes to `EXPLAIN` output (David Rowley, Tatsuo Ishii) [§](https://postgr.es/c/1eff8279d) [§](https://postgr.es/c/53abb1e0e) [§](https://postgr.es/c/95d6e9af0) [§](https://postgr.es/c/40708acd6)
* Add details about window function arguments to `EXPLAIN` output (Tom Lane) [§](https://postgr.es/c/8b1b34254)
* Add `Parallel Bitmap Heap Scan` worker cache statistics to `EXPLAIN ANALYZE` (David Geier, Heikki Linnakangas, Donghang Lin, Alena Rybakina, David Rowley) [§](https://postgr.es/c/5a1e6df3b)
* Indicate disabled nodes in `EXPLAIN ANALYZE` output (Robert Haas, David Rowley, Laurenz Albe) [§](https://postgr.es/c/c01743aa4) [§](https://postgr.es/c/161320b4b) [§](https://postgr.es/c/84b8fccbe)

### E.6.3.3. Data Types [#](#RELEASE-18-DATATYPES)

* Improve [Unicode](/server-administration/charset/collation.md#COLLATION-MANAGING-STANDARD) full case mapping and conversion (Jeff Davis) [§](https://postgr.es/c/4e7f62bc3) [§](https://postgr.es/c/286a365b9)

  This adds the ability to do conditional and title case mapping, and case map single characters to multiple characters.
* Allow [`jsonb`](/the-sql-language/datatype/datatype-json.md) `null` values to be cast to scalar types as `NULL` (Tom Lane) [§](https://postgr.es/c/a5579a90a)

  Previously such casts generated an error.
* Add optional parameter to [`json{b}_strip_nulls`](/the-sql-language/functions/functions-json.md#FUNCTIONS-JSON-PROCESSING-TABLE) to allow removal of null array elements (Florents Tselai) [§](https://postgr.es/c/4603903d2)
* Add function [`array_sort()`](/the-sql-language/functions/functions-array.md#ARRAY-FUNCTIONS-TABLE) which sorts an array's first dimension (Junwang Zhao, Jian He) [§](https://postgr.es/c/6c12ae09f)
* Add function [`array_reverse()`](/the-sql-language/functions/functions-array.md#ARRAY-FUNCTIONS-TABLE) which reverses an array's first dimension (Aleksander Alekseev) [§](https://postgr.es/c/49d6c7d8d)
* Add function [`reverse()`](/the-sql-language/functions/functions-string.md#FUNCTIONS-STRING-OTHER) to reverse bytea bytes (Aleksander Alekseev) [§](https://postgr.es/c/0697b2390)
* Allow casting between integer types and [`bytea`](/the-sql-language/datatype/datatype-binary.md) (Aleksander Alekseev) [§](https://postgr.es/c/6da469bad)

  The integer values are stored as `bytea` two's complement values.
* Update Unicode data to [Unicode](/server-administration/charset/collation.md#COLLATION-MANAGING-STANDARD) 16.0.0 (Peter Eisentraut) [§](https://postgr.es/c/82a46cca9)
* Add full text search [stemming](/the-sql-language/textsearch/textsearch-dictionaries.md#TEXTSEARCH-SNOWBALL-DICTIONARY) for Estonian (Tom Lane) [§](https://postgr.es/c/b464e51ab)
* Improve the [`XML`](/the-sql-language/datatype/datatype-xml.md) error codes to more closely match the SQL standard (Tom Lane) [§](https://postgr.es/c/cd838e200)

  These errors are reported via [`SQLSTATE`](/appendixes/errcodes-appendix.md).

### E.6.3.4. Functions [#](#RELEASE-18-FUNCTIONS)

* Add function [`casefold()`](/the-sql-language/functions/functions-string.md#FUNCTIONS-STRING-OTHER) to allow for more sophisticated case-insensitive matching (Jeff Davis) [§](https://postgr.es/c/bfc599206)

  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()`](/the-sql-language/functions/functions-aggregate.md#FUNCTIONS-AGGREGATE-TABLE)/[`MAX()`](/the-sql-language/functions/functions-aggregate.md#FUNCTIONS-AGGREGATE-TABLE) aggregates on arrays and composite types (Aleksander Alekseev, Marat Buharov) [§](https://postgr.es/c/a0f1fce80) [§](https://postgr.es/c/2d24fd942)
* Add a `WEEK` option to [`EXTRACT()`](/the-sql-language/functions/functions-datetime.md#FUNCTIONS-DATETIME-EXTRACT) (Tom Lane) [§](https://postgr.es/c/6be39d77a)
* Improve the output `EXTRACT(QUARTER ...)` for negative values (Tom Lane) [§](https://postgr.es/c/6be39d77a)
* Add roman numeral support to [`to_number()`](/the-sql-language/functions/functions-formatting.md#FUNCTIONS-FORMATTING-TABLE) (Hunaid Sohail) [§](https://postgr.es/c/172e6b3ad)

  This is accessed via the `RN` pattern.
* Add [`UUID`](/the-sql-language/datatype/datatype-uuid.md) version 7 generation function [`uuidv7()`](/the-sql-language/functions/functions-uuid.md#FUNC_UUID_GEN_TABLE) (Andrey Borodin) [§](https://postgr.es/c/78c5e141e)

  This `UUID` value is temporally sortable. Function alias [`uuidv4()`](/the-sql-language/functions/functions-uuid.md#FUNC_UUID_GEN_TABLE) has been added to explicitly generate version 4 UUIDs.
* Add functions [`crc32()`](/the-sql-language/functions/functions-binarystring.md#FUNCTIONS-BINARYSTRING-OTHER) and [`crc32c()`](/the-sql-language/functions/functions-binarystring.md#FUNCTIONS-BINARYSTRING-OTHER) to compute CRC values (Aleksander Alekseev) [§](https://postgr.es/c/760162fed)
* Add math functions [`gamma()`](/the-sql-language/functions/functions-math.md#FUNCTIONS-MATH-FUNC-TABLE) and [`lgamma()`](/the-sql-language/functions/functions-math.md#FUNCTIONS-MATH-FUNC-TABLE) (Dean Rasheed) [§](https://postgr.es/c/a3b6dfd41)
* Allow `=>` syntax for named cursor arguments in [PL/pgSQL](/server-programming/plpgsql.md) (Pavel Stehule) [§](https://postgr.es/c/246dedc5d)

  We previously only accepted `:=`.
* Allow [`regexp_match[es]()`](/the-sql-language/functions/functions-matching.md#FUNCTIONS-POSIX-REGEXP)/[`regexp_like()`](/the-sql-language/functions/functions-matching.md#FUNCTIONS-POSIX-REGEXP)/[`regexp_replace()`](/the-sql-language/functions/functions-matching.md#FUNCTIONS-POSIX-REGEXP)/[`regexp_count()`](/the-sql-language/functions/functions-matching.md#FUNCTIONS-POSIX-REGEXP)/[`regexp_instr()`](/the-sql-language/functions/functions-matching.md#FUNCTIONS-POSIX-REGEXP)/[`regexp_substr()`](/the-sql-language/functions/functions-matching.md#FUNCTIONS-POSIX-REGEXP)/[`regexp_split_to_table()`](/the-sql-language/functions/functions-matching.md#FUNCTIONS-POSIX-REGEXP)/[`regexp_split_to_array()`](/the-sql-language/functions/functions-matching.md#FUNCTIONS-POSIX-REGEXP) to use named arguments (Jian He) [§](https://postgr.es/c/580f8727c)

### E.6.3.5. [Libpq](/client-interfaces/libpq.md) [#](#RELEASE-18-LIBPQ)

* Add function [`PQfullProtocolVersion()`](/client-interfaces/libpq/libpq-status.md#LIBPQ-PQFULLPROTOCOLVERSION) to report the full, including minor, protocol version number (Jacob Champion, Jelte Fennema-Nio) [§](https://postgr.es/c/cdb6b0fdb)
* Add libpq connection [parameters](/client-interfaces/libpq/libpq-connect.md#LIBPQ-CONNECT-SSL-MAX-PROTOCOL-VERSION) and [environment variables](/client-interfaces/libpq/libpq-envars.md) to specify the minimum and maximum acceptable protocol version for connections (Jelte Fennema-Nio) [§](https://postgr.es/c/285613c60) [§](https://postgr.es/c/507034910)
* Report [search\_path](/server-administration/runtime-config/runtime-config-client.md#GUC-SEARCH-PATH) changes to the client (Alexander Kukushkin, Jelte Fennema-Nio, Tomas Vondra) [§](https://postgr.es/c/28a1121fd) [§](https://postgr.es/c/0d06a7eac)
* Add [`PQtrace()`](/client-interfaces/libpq/libpq-control.md#LIBPQ-PQTRACE) output for all message types, including authentication (Jelte Fennema-Nio) [§](https://postgr.es/c/ea92f3a0a) [§](https://postgr.es/c/a5c6b8f22) [§](https://postgr.es/c/b8b3f861f) [§](https://postgr.es/c/e87c14b19) [§](https://postgr.es/c/7adec2d5f)
* Add libpq connection parameter [`sslkeylogfile`](/client-interfaces/libpq/libpq-connect.md#LIBPQ-CONNECT-SSLKEYLOGFILE) which dumps out SSL key material (Abhishek Chanda, Daniel Gustafsson) [§](https://postgr.es/c/2da74d8d6)

  This is useful for debugging.
* Modify some libpq function signatures to use `int64_t` (Thomas Munro) [§](https://postgr.es/c/3c86223c9)

  These previously used `pg_int64`, which is now deprecated.

### E.6.3.6. [psql](/reference/reference-client/app-psql.md) [#](#RELEASE-18-PSQL)

* Allow psql to parse, bind, and close named prepared statements (Anthonin Bonnefoy, Michael Paquier) [§](https://postgr.es/c/d55322b0d) [§](https://postgr.es/c/fc39b286a)

  This is accomplished with new commands [`\parse`](/reference/reference-client/app-psql.md#APP-PSQL-META-COMMAND-PARSE), [`\bind_named`](/reference/reference-client/app-psql.md#APP-PSQL-META-COMMAND-BIND-NAMED), and [`\close_prepared`](/reference/reference-client/app-psql.md#APP-PSQL-META-COMMAND-CLOSE-PREPARED).
* Add psql backslash commands to allowing issuance of pipeline queries (Anthonin Bonnefoy) [§](https://postgr.es/c/41625ab8e) [§](https://postgr.es/c/17caf6644) [§](https://postgr.es/c/2cce0fe44)

  The new commands are [`\startpipeline`](/reference/reference-client/app-psql.md#APP-PSQL-META-COMMAND-PIPELINE), `\syncpipeline`, `\sendpipeline`, `\endpipeline`, `\flushrequest`, `\flush`, and `\getresults`.
* Allow adding pipeline status to the psql prompt and add related state variables (Anthonin Bonnefoy) [§](https://postgr.es/c/3ce357584)

  The new prompt character is `%P` and the new psql variables are [`PIPELINE_SYNC_COUNT`](/reference/reference-client/app-psql.md#APP-PSQL-VARIABLES-PIPELINE-SYNC-COUNT), [`PIPELINE_COMMAND_COUNT`](/reference/reference-client/app-psql.md#APP-PSQL-VARIABLES-PIPELINE-COMMAND-COUNT), and [`PIPELINE_RESULT_COUNT`](/reference/reference-client/app-psql.md#APP-PSQL-VARIABLES-PIPELINE-RESULT-COUNT).
* Allow adding the connection service name to the psql prompt or access it via psql variable (Michael Banck) [§](https://postgr.es/c/477728b5d)
* Add psql option to use expanded mode on all list commands (Dean Rasheed) [§](https://postgr.es/c/00f4c2959)

  Adding backslash suffix `x` enables this.
* Change psql's [`\conninfo`](/reference/reference-client/app-psql.md#APP-PSQL-META-COMMAND-CONNINFO) to use tabular format and include more information (Álvaro Herrera, Maiquel Grassi, Hunaid Sohail) [§](https://postgr.es/c/bba2fbc62)
* Add function's leakproof indicator to psql's [`\df+`](/reference/reference-client/app-psql.md#APP-PSQL-META-COMMAND-DF-LC), `\do+`, `\dAo+`, and `\dC+` outputs (Yugo Nagata) [§](https://postgr.es/c/2355e5111)
* Add access method details for partitioned relations in [`\dP+`](/reference/reference-client/app-psql.md#APP-PSQL-META-COMMAND-DP-UC) (Justin Pryzby) [§](https://postgr.es/c/978f38c77)
* Add `default_version` to the psql [`\dx`](/reference/reference-client/app-psql.md#APP-PSQL-META-COMMAND-DX-LC) extension output (Magnus Hagander) [§](https://postgr.es/c/d696406a9)
* Add psql variable [`WATCH_INTERVAL`](/reference/reference-client/app-psql.md#APP-PSQL-VARIABLES-WATCH-INTERVAL) to set the default [`\watch`](/reference/reference-client/app-psql.md#APP-PSQL-META-COMMAND-WATCH) wait time (Daniel Gustafsson) [§](https://postgr.es/c/1a759c832)

### E.6.3.7. Server Applications [#](#RELEASE-18-SERVER-APPS)

* Change [initdb](/reference/reference-server/app-initdb.md) to default to enabling checksums (Greg Sabino Mullane) [§](https://postgr.es/c/983a588e0) [§](https://postgr.es/c/04bec894a)

  The new initdb option `--no-data-checksums` disables checksums.
* Add initdb option `--no-sync-data-files` to avoid syncing heap/index files (Nathan Bossart) [§](https://postgr.es/c/cf131fa94)

  initdb option `--no-sync` is still available to avoid syncing any files.
* Add [vacuumdb](/reference/reference-client/app-vacuumdb.md) option `--missing-stats-only` to compute only missing optimizer statistics (Corey Huinker, Nathan Bossart) [§](https://postgr.es/c/edba754f0) [§](https://postgr.es/c/987910502)

  This option can only be run by superusers and can only be used with options `--analyze-only` and `--analyze-in-stages`.
* Add [pg\_combinebackup](/reference/reference-client/app-pgcombinebackup.md) option `-k`/`--link` to enable hard linking (Israel Barth Rubio, Robert Haas) [§](https://postgr.es/c/99aeb8470)

  Only some files can be hard linked. This should not be used if the backups will be used independently.
* Allow [pg\_verifybackup](/reference/reference-client/app-pgverifybackup.md) to verify tar-format backups (Amul Sul) [§](https://postgr.es/c/8dfd31290)
* If [pg\_rewind](/reference/reference-server/app-pgrewind.md)'s `--source-server` specifies a database name, use it in `--write-recovery-conf` output (Masahiko Sawada) [§](https://postgr.es/c/4ecdd4110)
* Add [pg\_resetwal](/reference/reference-server/app-pgresetwal.md) option `--char-signedness` to change the default `char` signedness (Masahiko Sawada) [§](https://postgr.es/c/30666d185)

#### E.6.3.7.1. [pg\_dump](/reference/reference-client/app-pgdump.md)/[pg\_dumpall](/reference/reference-client/app-pg-dumpall.md)/[pg\_restore](/reference/reference-client/app-pgrestore.md) [#](#RELEASE-18-PGDUMP)

* Add [pg\_dump](/reference/reference-client/app-pgdump.md) option `--statistics` (Jeff Davis) [§](https://postgr.es/c/bde2fb797) [§](https://postgr.es/c/a3e8dc143)
* Add pg\_dump and [pg\_dumpall](/reference/reference-client/app-pg-dumpall.md) option `--sequence-data` to dump sequence data that would normally be excluded (Nathan Bossart) [§](https://postgr.es/c/9c49f0e8c) [§](https://postgr.es/c/acea3fc49)
* Add [pg\_dump](/reference/reference-client/app-pgdump.md), [pg\_dumpall](/reference/reference-client/app-pg-dumpall.md), and [pg\_restore](/reference/reference-client/app-pgrestore.md) options `--statistics-only`, `--no-statistics`, `--no-data`, and `--no-schema` (Corey Huinker, Jeff Davis) [§](https://postgr.es/c/1fd1bd871)
* Add option `--no-policies` to disable row level security policy processing in [pg\_dump](/reference/reference-client/app-pgdump.md), [pg\_dumpall](/reference/reference-client/app-pg-dumpall.md), [pg\_restore](/reference/reference-client/app-pgrestore.md) (Nikolay Samokhvalov) [§](https://postgr.es/c/cd3c45125)

  This is useful for migrating to systems with different policies.

#### E.6.3.7.2. [pg\_upgrade](/reference/reference-server/pgupgrade.md) [#](#RELEASE-18-PGUPGRADE)

* Allow pg\_upgrade to preserve optimizer statistics (Corey Huinker, Jeff Davis, Nathan Bossart) [§](https://postgr.es/c/1fd1bd871) [§](https://postgr.es/c/c9d502eb6) [§](https://postgr.es/c/d5f1b6a75) [§](https://postgr.es/c/1fd1bd871)

  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) [§](https://postgr.es/c/40e2e5e92) [§](https://postgr.es/c/6d3d2e8e5) [§](https://postgr.es/c/7baa36de5) [§](https://postgr.es/c/46cad8b31) [§](https://postgr.es/c/6ab8f27bc) [§](https://postgr.es/c/bbf83cab9) [§](https://postgr.es/c/9db3018cf) [§](https://postgr.es/c/c34eabfbb) [§](https://postgr.es/c/cf2f82a37) [§](https://postgr.es/c/f93f5f7b9) [§](https://postgr.es/c/c880cf258)

  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) [§](https://postgr.es/c/626d7236b)

  This mode is potentially the fastest.
* Add pg\_upgrade option `--set-char-signedness` to set the default `char` signedness of new cluster (Masahiko Sawada) [§](https://postgr.es/c/a8238f87f) [§](https://postgr.es/c/1aab68059)

  This is to handle cases where a pre-PostgreSQL 18 cluster's default CPU signedness does not match the new cluster.

#### E.6.3.7.3. Logical Replication Applications [#](#RELEASE-18-LOGICALREP-APP)

* Add [pg\_createsubscriber](/reference/reference-server/app-pgcreatesubscriber.md) option `--all` to create logical replicas for all databases (Shubham Khanna) [§](https://postgr.es/c/fb2ea12f4)
* Add pg\_createsubscriber option `--clean` to remove publications (Shubham Khanna) [§](https://postgr.es/c/e5aeed4b8) [§](https://postgr.es/c/60dda7bbc)
* Add pg\_createsubscriber option `--enable-two-phase` to enable prepared transactions (Shubham Khanna) [§](https://postgr.es/c/e117cfb2f)
* Add [pg\_recvlogical](/reference/reference-client/app-pgrecvlogical.md) option `--enable-failover` to specify failover slots (Hayato Kuroda) [§](https://postgr.es/c/cf2655a90)

  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) [§](https://postgr.es/c/c68100aa4)

### E.6.3.8. Source Code [#](#RELEASE-18-SOURCE-CODE)

* Separate the loading and running of [injection points](/server-programming/extend/xfunc-c.md#XFUNC-ADDIN-INJECTION-POINTS) (Michael Paquier, Heikki Linnakangas) [§](https://postgr.es/c/4b211003e) [§](https://postgr.es/c/a0a5869a8)

  Injection points can now be created, but not run, via [`INJECTION_POINT_LOAD()`](/server-programming/extend/xfunc-c.md#XFUNC-ADDIN-INJECTION-POINTS), and such injection points can be run via [`INJECTION_POINT_CACHED()`](/server-programming/extend/xfunc-c.md#XFUNC-ADDIN-INJECTION-POINTS).
* Support runtime arguments in injection points (Michael Paquier) [§](https://postgr.es/c/371f2db8b)
* Allow inline injection point test code with [`IS_INJECTION_POINT_ATTACHED()`](/server-programming/extend/xfunc-c.md#XFUNC-ADDIN-INJECTION-POINTS) (Heikki Linnakangas) [§](https://postgr.es/c/20e0e7da9)
* Improve the performance of processing long [`JSON`](/the-sql-language/datatype/datatype-json.md) strings using SIMD (Single Instruction Multiple Data) (David Rowley) [§](https://postgr.es/c/ca6fde922)
* Speed up CRC32C calculations using x86 AVX-512 instructions (Raghuveer Devulapalli, Paul Amonson) [§](https://postgr.es/c/3c6e8c123)
* Add ARM Neon and SVE CPU intrinsics for popcount (integer bit counting) (Chiranmoy Bhattacharya, Devanga Susmitha, Rama Malladi) [§](https://postgr.es/c/6be53c276) [§](https://postgr.es/c/519338ace)
* Improve the speed of numeric multiplication and division (Joel Jacobson, Dean Rasheed) [§](https://postgr.es/c/ca481d3c9) [§](https://postgr.es/c/c4e44224c) [§](https://postgr.es/c/8dc28d7eb) [§](https://postgr.es/c/9428c001f)
* Add configure option [`--with-libnuma`](/server-administration/installation/install-make.md#CONFIGURE-OPTION-WITH-LIBNUMA) to enable NUMA awareness (Jakub Wartak, Bertrand Drouvot) [§](https://postgr.es/c/65c298f61) [§](https://postgr.es/c/8cc139bec) [§](https://postgr.es/c/ba2a3c230)

  The function [`pg_numa_available()`](/the-sql-language/functions/functions-info.md#FUNCTIONS-INFO-SESSION-TABLE) reports on NUMA awareness, and system views [`pg_shmem_allocations_numa`](/internals/views/view-pg-shmem-allocations-numa.md) and [`pg_buffercache_numa`](/appendixes/contrib/pgbuffercache.md#PGBUFFERCACHE-PG-BUFFERCACHE-NUMA) which report on shared memory distribution across NUMA nodes.
* Add [TOAST](/internals/storage/storage-toast.md) table to [`pg_index`](/internals/catalogs/catalog-pg-index.md) to allow for very large expression indexes (Nathan Bossart) [§](https://postgr.es/c/b52c4fc3c)
* Remove column [`pg_attribute`](/internals/catalogs/catalog-pg-attribute.md).`attcacheoff` (David Rowley) [§](https://postgr.es/c/02a8d0c45)
* Add column [`pg_class`](/internals/catalogs/catalog-pg-class.md).`relallfrozen` (Melanie Plageman) [§](https://postgr.es/c/99f8f3fbb)
* Add [`amgettreeheight`](/internals/indexam.md), `amconsistentequality`, and `amconsistentordering` to the index access method API (Mark Dilger) [§](https://postgr.es/c/56fead44d) [§](https://postgr.es/c/af4002b38)
* Add GiST support function [`stratnum()`](/internals/indextypes/gist.md#GIST-EXTENSIBILITY) (Paul A. Jungwirth) [§](https://postgr.es/c/7406ab623)
* Record the default CPU signedness of `char` in [pg\_controldata](/reference/reference-server/app-pgcontroldata.md) (Masahiko Sawada) [§](https://postgr.es/c/44fe30fda)
* Add support for Python "Limited API" in [PL/Python](/server-programming/plpython.md) (Peter Eisentraut) [§](https://postgr.es/c/72a3d0462) [§](https://postgr.es/c/0793ab810)

  This helps prevent problems caused by Python 3.x version mismatches.
* Change the minimum supported Python version to 3.6.8 (Jacob Champion) [§](https://postgr.es/c/45363fca6)
* Remove support for OpenSSL versions older than 1.1.1 (Daniel Gustafsson) [§](https://postgr.es/c/a70e01d43) [§](https://postgr.es/c/6c66b7443)
* If LLVM is enabled, require version 14 or later (Thomas Munro) [§](https://postgr.es/c/972c2cd28)
* Add macro [`PG_MODULE_MAGIC_EXT`](/the-sql-language/functions/functions-info.md) to allow extensions to report their name and version (Andrei Lepikhov) [§](https://postgr.es/c/9324c8c58)

  This information can be access via the new function [`pg_get_loaded_modules()`](/the-sql-language/functions/functions-info.md#FUNCTIONS-INFO-SESSION-TABLE).
* Document that [`SPI_connect()`](/server-programming/spi/spi-interface/spi-spi-connect.md)/[`SPI_connect_ext()`](/server-programming/spi/spi-interface/spi-spi-connect.md) always returns success (`SPI_OK_CONNECT`) (Stepan Neretin) [§](https://postgr.es/c/218527d01)

  Errors are always reported via `ereport()`.
* Add [documentation section](/server-programming/extend/xfunc-c.md#XFUNC-API-ABI-STABILITY-GUIDANCE) about API and ABI compatibility (David Wheeler, Peter Eisentraut) [§](https://postgr.es/c/e54a42ac9)
* Remove the experimental designation of Meson builds on Windows (Aleksander Alekseev) [§](https://postgr.es/c/5afaba629)
* Remove configure options `--disable-spinlocks` and `--disable-atomics` (Thomas Munro) [§](https://postgr.es/c/e25626677) [§](https://postgr.es/c/813852613)

  Thirty-two-bit atomic operations are now required.
* Remove support for the HPPA/PA-RISC architecture (Tom Lane) [§](https://postgr.es/c/edadeb071)

### E.6.3.9. Additional Modules [#](#RELEASE-18-MODULES)

* Add extension [pg\_logicalinspect](/appendixes/contrib/pglogicalinspect.md) to inspect logical snapshots (Bertrand Drouvot) [§](https://postgr.es/c/7cdfeee32)
* Add extension [pg\_overexplain](/appendixes/contrib/pgoverexplain.md) which adds debug details to [`EXPLAIN`](/reference/sql-commands/sql-explain.md) output (Robert Haas) [§](https://postgr.es/c/8d5ceb113)
* Add output columns to [`postgres_fdw_get_connections()`](/appendixes/contrib/postgres-fdw.md#POSTGRES-FDW-FUNCTIONS) (Hayato Kuroda, Sagar Dilip Shedge) [§](https://postgr.es/c/c297a47c5) [§](https://postgr.es/c/857df3cef) [§](https://postgr.es/c/4f08ab554) [§](https://postgr.es/c/fe186bda7)

  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](/server-administration/client-authentication/auth-password.md) authentication from the client to be passed to [postgres\_fdw](/appendixes/contrib/postgres-fdw.md) servers (Matheus Alcantara, Peter Eisentraut) [§](https://postgr.es/c/761c79508)

  This avoids storing postgres\_fdw authentication information in the database, and is enabled with the postgres\_fdw [`use_scram_passthrough`](/appendixes/contrib/postgres-fdw.md#POSTGRES-FDW-OPTION-USE-SCRAM-PASSTHROUGH) connection option. libpq uses new connection parameters [scram\_client\_key](/client-interfaces/libpq/libpq-connect.md#LIBPQ-CONNECT-SCRAM-CLIENT-KEY) and [scram\_server\_key](/client-interfaces/libpq/libpq-connect.md#LIBPQ-CONNECT-SCRAM-SERVER-KEY).
* Allow SCRAM authentication from the client to be passed to [dblink](/appendixes/contrib/dblink.md) servers (Matheus Alcantara) [§](https://postgr.es/c/3642df265)
* Add `on_error` and `log_verbosity` options to [file\_fdw](/appendixes/contrib/file-fdw.md) (Atsushi Torikoshi) [§](https://postgr.es/c/a1c4c8a9e)

  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) [§](https://postgr.es/c/6c8f67032)

  This is active when `ON_ERROR = 'ignore'`.
* Add configurable variable `min_password_length` to [passwordcheck](/appendixes/contrib/passwordcheck.md) (Emanuele Musella, Maurizio Boriani) [§](https://postgr.es/c/f7e1b3828)

  This controls the minimum password length.
* Have [pgbench](/reference/reference-client/pgbench.md) report the number of failed, retried, or skipped transactions in per-script reports (Yugo Nagata) [§](https://postgr.es/c/cae0f3c40)
* Add [isn](/appendixes/contrib/isn.md) server variable `weak` to control invalid check digit acceptance (Viktor Holmberg) [§](https://postgr.es/c/448904423)

  This was previously only controlled by function [`isn_weak()`](/appendixes/contrib/isn.md#ISN-FUNCTIONS).
* Allow values to be sorted to speed [btree\_gist](/appendixes/contrib/btree-gist.md) index builds (Bernd Helmle, Andrey Borodin) [§](https://postgr.es/c/e4309f73f)
* Add [amcheck](/appendixes/contrib/amcheck.md) check function [`gin_index_check()`](/appendixes/contrib/amcheck.md#AMCHECK-FUNCTIONS) to verify `GIN` indexes (Grigory Kryachko, Heikki Linnakangas, Andrey Borodin) [§](https://postgr.es/c/14ffaece0)
* Add functions [`pg_buffercache_evict_relation()`](/appendixes/contrib/pgbuffercache.md#PGBUFFERCACHE-PG-BUFFERCACHE-EVICT-RELATION) and [`pg_buffercache_evict_all()`](/appendixes/contrib/pgbuffercache.md#PGBUFFERCACHE-PG-BUFFERCACHE-EVICT-ALL) to evict unpinned shared buffers (Nazir Bilal Yavuz) [§](https://postgr.es/c/dcf7e1697)

  The existing function [`pg_buffercache_evict()`](/appendixes/contrib/pgbuffercache.md#PGBUFFERCACHE-PG-BUFFERCACHE-EVICT) now returns the buffer flush status.
* Allow extensions to install custom [EXPLAIN](/reference/sql-commands/sql-explain.md) options (Robert Haas, Sami Imseih) [§](https://postgr.es/c/c65bc2e1d) [§](https://postgr.es/c/4fd02bf7c) [§](https://postgr.es/c/50ba65e73)
* Allow extensions to use the server's cumulative statistics API (Michael Paquier) [§](https://postgr.es/c/7949d9594) [§](https://postgr.es/c/2eff9e678)

#### E.6.3.9.1. [pg\_stat\_statements](/appendixes/contrib/pgstatstatements.md) [#](#RELEASE-18-PGSTATSTATEMENTS)

* Allow the queries of [CREATE TABLE AS](/reference/sql-commands/sql-createtableas.md) and [DECLARE](/reference/sql-commands/sql-declare.md) to be tracked by pg\_stat\_statements (Anthonin Bonnefoy) [§](https://postgr.es/c/6b652e6ce)

  They are also now assigned query ids.
* Allow the parameterization of [SET](/reference/sql-commands/sql-set.md) values in pg\_stat\_statements (Greg Sabino Mullane, Michael Paquier) [§](https://postgr.es/c/dc6851596)

  This reduces the bloat caused by `SET` statements with differing constants.
* Add [`pg_stat_statements`](/appendixes/contrib/pgstatstatements.md#PGSTATSTATEMENTS-PG-STAT-STATEMENTS) columns to report parallel activity (Guillaume Lelarge) [§](https://postgr.es/c/cf54a2c00)

  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) [§](https://postgr.es/c/ce5bcc4a9)

#### E.6.3.9.2. [pgcrypto](/appendixes/contrib/pgcrypto.md) [#](#RELEASE-18-PGCRYPTO)

* Add pgcrypto algorithms [`sha256crypt`](/appendixes/contrib/pgcrypto.md#PGCRYPTO-CRYPT-ALGORITHMS) and [`sha512crypt`](/appendixes/contrib/pgcrypto.md#PGCRYPTO-CRYPT-ALGORITHMS) (Bernd Helmle) [§](https://postgr.es/c/749a9e20c)
* Add [CFB](/appendixes/contrib/pgcrypto.md#PGCRYPTO-RAW-ENC-FUNCS) mode to pgcrypto encryption and decryption (Umar Hayat) [§](https://postgr.es/c/9ad1b3d01)
* Add function [`fips_mode()`](/appendixes/contrib/pgcrypto.md#PGCRYPTO-OPENSSL-SUPPORT-FUNCS) to report the server's FIPS mode (Daniel Gustafsson) [§](https://postgr.es/c/924d89a35)
* Add pgcrypto server variable [`builtin_crypto_enabled`](/appendixes/contrib/pgcrypto.md#PGCRYPTO-CONFIGURATION-PARAMETERS-BUILTIN_CRYPTO_ENABLED) to allow disabling builtin non-FIPS mode cryptographic functions (Daniel Gustafsson, Joe Conway) [§](https://postgr.es/c/035f99cbe)

  This is useful for guaranteeing FIPS mode behavior.

## E.6.4. Acknowledgments [#](#RELEASE-18-ACKNOWLEDGEMENTS)

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               |

***

原文：[PostgreSQL 18.6 Documentation](https://www.postgresql.org/docs/18/release-18.html)（英文原文，待翻譯）


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