From a724c7889f74cc4e76e1979f90808decbc744c79 Mon Sep 17 00:00:00 2001 From: Bruce Momjian Date: Thu, 1 May 2025 22:36:58 -0400 Subject: [PATCH] doc: first draft of the PG 18 release notes --- doc/src/sgml/release-18.sgml | 3511 +++++++++++++++++++++++++++++++++- 1 file changed, 3501 insertions(+), 10 deletions(-) diff --git a/doc/src/sgml/release-18.sgml b/doc/src/sgml/release-18.sgml index 4f027a07d1ce..6faca897689c 100644 --- a/doc/src/sgml/release-18.sgml +++ b/doc/src/sgml/release-18.sgml @@ -1,16 +1,3507 @@ - - Release 18 + + Release 18 - - Release date: - 2025-??-?? - + + Release date: + 2025-??-??, CURRENT AS OF 2025-05-01 + - - This is just a placeholder for now. - + + Overview - + + PostgreSQL 18 contains many new features + and enhancements, including: + + + + + + + (to be completed) + + + + + + The above items and other new features of + PostgreSQL 18 are explained in more detail + in the sections below. + + + + + + + Migration to Version 18 + + + A dump/restore using or use of + or logical replication is required for + those wishing to migrate data from any previous release. See 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 time zone abbreviation handling (Tom Lane) +§ + + + +The system will now favor time zone abbreviation for the current session time zone before checking the server variable timezone_abbreviations. Previously timezone_abbreviations were +consulted first for matches. + + + + + + + +Deprecate MD5 password authentication (Nathan Bossart) +§ + + + +Warnings generated by their use can be disabled by the server variable md5_password_warnings. + + + + + + + +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 IN 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 Postgres 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. + + + + + + + +Remove non-functioning support for RULE privileges in GRANT/REVOKE (Fujii Masao) +§ + + + +These have been non-functioning since Postgres 8.2. + + + + + + + +Rename server variable ssl_ecdh_curve to ssl_groups and allow multiple colon-separated ECDH curves to be specified (Erica Zhang, Daniel Gustafsson) +§ + + + + + + + +Remove column pg_backend_memory_contexts.parent (Melih Mutlu) +§ + + + +This is now longer needed since pg_backend_memory_contexts.path was added. + + + + + + + +Change pg_backend_memory_contexts.level to be one-based (Melih Mutlu) +§ + + + +It was previously zero-based. + + + + + + + + + Changes + + + Below you will find a detailed account of the changes between + PostgreSQL 18 and the previous major + release. + + + + Server + + + Optimizer + + + + + + + +Remove some unnecessary table self-joins (Andrey Lepikhov, Alexander Kuzmenkov, Alexander Korotkov, Alena Rybakina) +§ + + + +This optimization can be disabled with 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) +§ + + + +The optimizer feature can be disabled via enable_distinct_reordering. + + + + + + + +Allow some HAVING clauses on GROUPING SETS to be pushed to WHERE clauses (Richard Guo) +§ + + + +This allows earlier row filtering. + + + + + + + +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 join to use incremental sorts (Richard Guo) +§ + + + + + + + +Improve the performance of hash joins (David Rowley) +§ + + + + + + +Allow partitions to be pruned earlier and quicker, and skipped in more places (Amit Langote, Ashutosh Bapat, Yuya Watari, David Rowley) +§ +§ +§ +§ +§ +§ + + + + + + + +Allow partitionwise join 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) +§ + + + + + + + + + Indexes + + + + + + + +Allow skip scans of btree indexes (Peter Geoghegan) +§ +§ +§ + + + +This is most useful if the earlier non-referenced columns contain few unique values. + + + + + + + +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 rangetype GiST and btree index builds (Bernd Helmle) +§ + + + + + + + + + General Performance + + + + + + + +Add an asynchronous I/O subsystem (Andres Freund, Thomas Munro, Nazir Bilal Yavuz, Melanie Plageman) +§ +§ +§ +§ +§ +§ +§ +§ +§ +§ +§ + + + +This is enabled by default and controlled 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) +§ + + + + + + + +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 vacuum_max_eager_freeze_failure_rate, 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 this 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. + + + + + + + + + Monitoring + + + + + + + +Change server variable log_connections to log connections more granularly (Melanie Plageman) +§ +§ + + + +This server variable was previously only boolean; these options are still supported. + + + + + + + +Add log_line_prefix escape "%L" to output the client IP address (Greg Sabino Mullane) +§ + + + + + + + +Add server variable log_lock_failure to log lock acquisition failures (Yuki Seino) +§ + + + +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 fields are total_vacuum_time, total_autovacuum_time, total_analyze_time, and total_autoanalyze_time. + + + + + + + +Add VACUUM and ANALYZE delay time reporting (Bertrand Drouvot, Nathan Bossart) +§ +§ + + + +This information appears in the autovacuum logs, the system views pg_stat_progress_vacuum and pg_stat_progress_analyze, and the output of VACUUM and ANALYZE when in VERBOSE mode. This +tracking must be enabled with the server variable track_cost_delay_timing. + + + + + + + +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 use separate shared buffer and SLRU buffer values. + + + + + + + +Add columns to pg_stat_database to report parallel workers activity (Benoit Lobréau) +§ + + + +The new columns are parallel_workers_to_launch and parallel_workers_launched. + + + + + + + +Add per-backend I/O statistics reporting (Bertrand Drouvot) +§ +§ + + + +The statistics are accessed via pg_stat_get_backend_io(). Per-backend 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) +§ + + + + + + + +Add function pg_stat_get_backend_wal() to return per-backend WAL statistics (Bertrand Drouvot) +§ + + + + + + + +Add function pg_ls_summariesdir() to specifically list the contents of PGDATA/pg_wal/summaries (Yushi Ogiwara) +§ + + + + + + + +Remove read/sync fields from pg_stat_wal (Bertrand Drouvot) +§ +§ + + + +This removes columns wal_write, wal_sync, wal_write_time, and wal_sync_time. + + + + + + + +Have query jumbling of arrays consider only the first and last array elements (Dmitry Dolgov, Sami Imseih) +§ +§ + + + +Jumbling is used by pg_stat_statements. + + + + + + + +Adjust query jumbling 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 function pg_get_process_memory_contexts() to report process memory context statistics (Rahila Syed) +§ +§ + + + + + + + +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) +§ + + + + + + + + + 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. + + + + + + + + + Server Configuration + + + + + + + +Add support for the "oauth" authentication (Jacob Champion, Daniel Gustafsson, Thomas Munro) +§ + + + +This adds an "oauth" authentication method to pg_hba.conf, a server variable oauth_validator_libraries to specify OAUTH libraries, a configure flag --with-libcurl to add the required +compile-time libraries, and libpq OAUTH options. + + + + + + + +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) +§ + + + + + + + +Add function pg_check_fipsmode() to report the server's FIPS mode (Daniel Gustafsson) +§ + + + + + + + +Make cancel request keys 256 bits (Heikki Linnakangas) +§ + + + +This is enabled when the libpq client and server are Postgres 18 or later. + + + + + + + +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 needed 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) +§ + + + + + + + + + Streaming Replication and Recovery + + + + + + + +Allow inactive replication slots to be automatically invalided 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. + + + + + + + + + <link linkend="logical-replication">Logical Replication</link> + + + + + + + +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 columns, generated and non-generated, are published. Without a published 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-Postgres subscribers which lack such a capability. + + + + + + + +Change the default CREATE SUBSCRIPTION streaming option from "off" to "parallel" (Hayato Kuroda, Masahiko Sawada, Peter Smith, Amit Kapila) +§ + + + + + + + +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. + + + + + + + + + + + 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, old values for DELETE; MERGE would return the appropriate value for the internal query executed. This new syntax +allows INSERT with an ON CONFLICT action to return old values, UPDATE to return old values, and DELETE to return new values if the query assigned to an ON DELETE row would return new +values. New syntax allows changeable relation aliases "old" and "new" to specify which values should be returned. + + + + + + + +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. + + + + + + + <link linkend="ddl-constraints">Constraints</link> + + + + + + + +Allow the specification of non-overlapping PRIMARY KEY and UNIQUE constraints (Paul A. Jungwirth) + + + +This is specified by WITHOUT OVERLAPS on the last column. + + + + + + + + +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. + + + + + + + +Allow CHECK and foreign key constraints to be specified as NOT ENFORCED (Amul Sul) +§ +§ + + + +This also adds column pg_constraint.conenforced. + + + + + + + +Allow ALTER TABLE to set the NOT VALID attribute of NOT NULL constraints (Rushabh Lathia, Jian He) +§ + + + + + + + +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. + + + + + + + +Allow modification of the inheritability of constraints (Suraj Kharage, Álvaro Herrera) +§ +§ + + + +The syntax is ALTER TABLE ... ALTER CONSTRAINT ... [NO] INHERIT. + + + + + + + +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. + + + + + + + + <link linkend="sql-copy"><command>COPY</command></link> + + + + + + + +Add REJECT_LIMIT to control the number of invalid rows COPY IN can ignore (Atsushi Torikoshi) +§ + + + +This is active when ON_ERROR = 'ignore'. + + + + + + + +Allow COPY TO to copy rows from populated materialized view (Jian He) +§ + + + + + + + +Add COPY log_verbosity level "silent" to suppress all log output (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. + + + + + + + + <link linkend="sql-explain"><command>EXPLAIN</command></link> + + + + + + + +Automatically include BUFFERS output in EXPLAIN ANALYZE (Guillaume Lelarge, David Rowley) +§ + + + + + + + +Add WAL, CPU, and average read statistics output EXPLAIN ANALYZE VERBOSE (Anthonin Bonnefoy) +§ +§ + + + + + + + +Add full WAL buffer count to EXPLAIN (WAL), VACUUM/ANALYZE (VERBOSE), and autovacuum log 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 in EXPLAIN (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) +§ +§ +§ + + + + + + + + + + + Data Types + + + + + + + +Add support for Unicode case folding (Jeff Davis) +§ + + + + + + + +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. + + + + + + + + + Functions + + + + + + + +Add function CASEFOLD() to allow for more sophisticated case-insensitive matching (Jeff Davis) +§ + + + +Allows more accurate comparison, 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 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 plpgsql (Pavel Stehule) +§ + + + +We previously only accepted ":=". + + + + + + + +Allow regexp_match[es]/regexp_like/regexp_replace/regexp_count/regexp_instr/regexp_substr/regexp_split_to_table/regexp_split_to_array() to use named arguments (Jian He) +§ + + + + + + + + + <link linkend="libpq">libpq</link> + + + + + + + +Add function PQfullProtocolVersion() to report the full, including minor, protocol version number (Jacob Champion, Jelte Fennema-Nio) +§ + + + + + + + +Add libpq functions and environment variables to specify the minimum and maximum acceptable protocol version for connections (Jelte Fennema-Nio) +§ + + + + + + + +Add libpq function PQservice() to return the connection service name (Michael Banck) +§ + + + + + + + +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. + + + + + + + + + <xref linkend="app-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. + + + + + + + +Add psql backslash commands to allowing issuance of pipeline queries (Anthonin Bonnefoy) +§ +§ +§ + + + +The new commands are \startpipeline, \syncpipeline, \sendpipeline, \endpipeline, \flushrequest, \flush, and \getresults. + + + + + + + +Add psql pipeline status to the 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 psql to display the connection service name in the psql prompt or access it via psql variable (Michael Banck) +§ + + + + + + + +Change psql's \conninfo to use tabular format and include more information (Álvaro Herrera, Maiquel Grassi, Hunaid Sohail) +§ + + + + + + + +Add psql option to use expanded mode on all list commands (Dean Rasheed) +§ + + + +Adding 'x' enables this. + + + + + + + +Add function leakproof indicator 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) +§ + + + + + + + + + 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 --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 used by --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, and 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 for --write-recovery-conf output (Masahiko Sawada) +§ + + + + + + + +Add pg_resetwal option --char-signedness to change the default char signedness (Masahiko Sawada) +§ + + + + + + + + <link linkend="app-pgdump"><application>pg_dump</application>, etc.</link> + + + + + + + +Allow pg_dumpall to dump in the same output formats as pg_dump supports (Mahendra Singh Thalor, Andrew Dunstan) +§ + + + +Also modify pg_restore to handle such dumps. Previously pg_dumpall only supported text format. + + + + + + + +Add pg_dump option --sequence-data to dump sequence data that would normally be excluded (Nathan Bossart) +§ + + + + + + + +Add pg_dump options --with-schema, --with-data, and --with_statistics (Jeff Davis) +§ + + + +The negative versions of these options already existed. + + + + + + + +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 pg_dump, pg_dumpall, pg_restore to avoid policy specification (Nikolay Samokhvalov) +§ + + + +This is useful for migrating to systems with different policies. + + + + + + + + + <link linkend="pgupgrade"><application>pg_upgrade</application></link> + + + + + + + +Allow pg_upgrade to preserve optimizer statistics (Corey Huinker, Jeff Davis, Nathan Bossart) +§ +§ +§ + + + +Extended statistics are not preserved. + + + + + + + +Add pg_upgrade option --no-statistics (Corey Huinker, Jeff Davis) +§ + + + + + + + +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-Postgres 18 cluster's default CPU signedness does not match the new cluster. + + + + + + + + + Logical Replication Applications> + + + + + + + +Add pg_createsubscriber option --all to create logical replicas for all databases (Shubham Khanna) +§ + + + + + + + +Add pg_createsubscriber option -R/--remove to remove publications (Shubham Khanna) +§ + + + + + + + +Add pg_createsubscriber option --enable-two-phase to enable prepared transactions (Shubham Khanna) +§ + + + + + + + +Add pg_recvlogical option --failover to specify failover slots (Hayato Kuroda) +§ + + + + + + + +Allow pg_recvlogical --drop-slot to work without --dbname (Hayato Kuroda) +§ + + + + + + + + + + + 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(). + + + + + + + +Allow inline injection point test code with IS_INJECTION_POINT_ATTACHED() (Heikki Linnakangas) +§ + + + + + + + +Improve the performance of processing long JSON strings using SIMD instructions (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 multiplication (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 index 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(). + + + + + + + +Remove the experimental designation of Meson builds on Windows (Aleksander Alekseev) +§ + + + + + + + +Add documentation section about API and ABI compatibility (David Wheeler, Peter Eisentraut) +§ + + + + + + + +Remove configure option --disable-spinlocks (Thomas Munro) +§ + + + + + + + +Remove configure option --disable-atomics (Thomas Munro) +§ + + + +Thirty-two bit atomic operations are now required. + + + + + + + +Remove support for HPPA/PA-RISC architecture (Tom Lane) +§ + + + + + + + + + Additional Modules + + + + + + + +Add extension pg_logicalinspect to inspect logical snapshots (Bertrand Drouvot) +§ + + + + + + + +Add extension pg_overexplain which allows for additional EXPLAIN output useful for debugging (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, and "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 REJECT_LIMIT to control the number of invalid rows file_fdw can ignore (Atsushi Torikoshi) +§ + + + +This is active when ON_ERROR = 'ignore'. + + + + + + + +Add on_error and log_verbosity options to file_fdw (Atsushi Torikoshi) +§ + + + +These control how file_fdw handles and reports invalid file rows. + + + + + + + +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 transactions (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 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 use the server's cumulative statistics API (Michael Paquier) +§ +§ + + + + + + + +Allow extensions to install custom EXPLAIN options (Robert Haas, Sami Imseih) +§ +§ +§ + + + + + + + <link linkend="pgstatstatements"><application>pg_stat_statements</application></link> + + + + + + + +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) +§ + + + + + + + + + <link linkend="pgcrypto"><application>pgcrypto</application></link> + + + + + + + +Add pgcrypto functions sha256crypt() and sha512crypt() (Bernd Helmle) +§ + + + + + + + +Add CFB mode to pgcrypto encryption and decryption (Umar Hayat) +§ + + + + + + + +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. + + + + + + + + + + + + Acknowledgments + + + The following individuals (in alphabetical order) have contributed + to this release as patch authors, committers, reviewers, testers, + or reporters of issues. + + + + (to be completed) + + + +