Release date: 2024-09-26
PostgreSQL 17 contains many new features and enhancements, including:
      New memory management system for VACUUM, which reduces
      memory consumption and can improve overall vacuuming performance.
     
      New SQL/JSON capabilities, including constructors,
      identity functions, and the JSON_TABLE()
      function, which converts JSON data into a table representation.
     
Various query performance improvements, including for sequential reads using streaming I/O, write throughput under high concurrency, and searches over multiple values in a btree index.
Logical replication enhancements, including:
Failover control
pg_createsubscriber, a utility that creates logical replicas from physical standbys
pg_upgrade now preserves logical replication slots on publishers and full subscription state on subscribers. This will allow upgrades to future major versions to continue logical replication without requiring copy to resynchronize.
      New client-side connection option, sslnegotiation=direct,
      that performs a direct TLS handshake to avoid a round-trip negotiation.
     
pg_basebackup now supports incremental backup.
      COPY adds a new option,
      ON_ERROR ignore, that allows a copy operation to
      continue in the event of an error.
     
The above items and other new features of PostgreSQL 17 are explained in more detail in the sections below.
A dump/restore using pg_dumpall or use of pg_upgrade or logical replication is required for those wishing to migrate data from any previous release. See Section 18.6 for general information on migrating to new major releases.
Version 17 contains a number of changes that may affect compatibility with previous releases. Observe the following incompatibilities:
Change functions to use a safe search_path during maintenance operations (Jeff Davis) § §
     This prevents maintenance operations (ANALYZE,
     CLUSTER, CREATE
     INDEX, CREATE
     MATERIALIZED VIEW, REFRESH
     MATERIALIZED VIEW, REINDEX,
     or VACUUM) from performing unsafe access.
     Functions used by expression indexes and materialized views that
     need to reference non-default schemas must specify a search path
     during function creation.
     
     Restrict ago to only appear at the end in
     interval values (Joseph Koshakow)
     §
     §
     
Also, prevent empty interval units from appearing multiple times.
Remove server variable old_snapshot_threshold (Thomas Munro) §
This variable allowed vacuum to remove rows that potentially could be still visible to running transactions, causing "snapshot too old" errors later if accessed. This feature might be re-added to PostgreSQL later if an improved implementation is found.
     Change SET
     SESSION AUTHORIZATION handling of the initial
     session user's superuser status (Joseph Koshakow)
     §
     
     The new behavior is based on the session user's superuser status at
     the time the SET SESSION AUTHORIZATION command
     is issued, rather than their superuser status at connection time.
     
Remove feature which simulated per-database users (Nathan Bossart) §
     The feature, db_user_namespace, was rarely used.
     
Remove adminpack contrib extension (Daniel Gustafsson) §
This was used by now end-of-life pgAdmin III.
     Remove wal_sync_method value
     fsync_writethrough on Windows (Thomas Munro)
     §
     
     This value was the same as fsync on Windows.
     
Change file boundary handling of two WAL file name functions (Kyotaro Horiguchi, Andres Freund, Bruce Momjian) §
     The functions pg_walfile_name()
     and pg_walfile_name_offset() used to report
     the previous LSN segment number when the
     LSN was on a file segment boundary;  it now
     returns the current LSN segment.
     
     Remove server variable trace_recovery_messages
     since it is no longer needed (Bharath Rupireddy)
     §
     
     Remove information schema column
     element_types.domain_default
     (Peter Eisentraut)
     §
     
Change pgrowlocks lock mode output labels (Bruce Momjian) §
     Remove buffers_backend and
     buffers_backend_fsync from pg_stat_bgwriter
     (Bharath Rupireddy)
     §
     
     These fields are considered redundant to similar columns in pg_stat_io.
     
Rename I/O block read/write timing statistics columns of pg_stat_statements (Nazir Bilal Yavuz) §
     This renames blk_read_time
     to shared_blk_read_time,
     and blk_write_time to
     shared_blk_write_time.
     
     Change pg_attribute.attstattarget
     and
     pg_statistic_ext.stxstattarget
     to represent the default statistics target as NULL
     (Peter Eisentraut)
     §
     §
     
     Rename pg_collation.colliculocale
     to colllocale and
     pg_database.daticulocale
     to datlocale (Jeff Davis)
     §
     
     Rename pg_stat_progress_vacuum
     column max_dead_tuples
     to max_dead_tuple_bytes,
     rename num_dead_tuples to
     num_dead_item_ids, and add
     dead_tuple_bytes (Masahiko Sawada)
     §
     §
     
     Rename SLRU columns in system view pg_stat_slru
     (Alvaro Herrera)
     §
     
     The column names accepted by pg_stat_reset_slru()
     are also changed.
     
Below you will find a detailed account of the changes between PostgreSQL 17 and the previous major release.
Allow the optimizer to improve CTE plans by considering the statistics and sort order of columns referenced in earlier row output clauses (Jian Guo, Richard Guo, Tom Lane) § §
       Improve optimization of IS NOT NULL and
       IS NULL query restrictions (David Rowley,
       Richard Guo, Andy Fan)
       §
       §
       
       Remove IS NOT NULL restrictions from queries on
       NOT NULL columns and eliminate scans on
       NOT NULL columns if IS NULL
       is specified.
       
       Allow partition pruning on boolean columns on IS [NOT]
       UNKNOWN conditionals (David Rowley)
       §
       
Improve optimization of range values when using containment operators <@ and @> (Kim Johan Andersson, Jian He) §
       Allow correlated IN subqueries to be transformed
       into joins (Andy Fan, Tom Lane)
       §
       
       Improve optimization of the LIMIT clause
       on partitioned tables, inheritance parents, and UNION
       ALL queries (Andy Fan, David Rowley)
       §
       
Allow query nodes to be run in parallel in more cases (Tom Lane) §
       Allow GROUP BY columns to be internally
       ordered to match ORDER BY (Andrei Lepikhov,
       Teodor Sigaev)
       §
       
This can be disabled using server variable enable_group_by_reordering.
       Allow UNION (without ALL)
       to use MergeAppend (David Rowley)
       §
       
Fix MergeAppend plans to more accurately compute the number of rows that need to be sorted (Alexander Kuzmenkov) §
Allow GiST and SP-GiST indexes to be part of incremental sorts (Miroslav Bendik) §
       This is particularly useful for ORDER BY
       clauses where the first column has a GiST and SP-GiST index,
       and other columns do not.
       
       Add columns to pg_stats
       to report range-type histogram information (Egor Rogov, Soumyadeep
       Chakraborty)
       §
       
Allow vacuum to more efficiently remove and freeze tuples (Melanie Plageman, Heikki Linnakangas) §
WAL traffic caused by vacuum is also more compact.
Allow vacuum to more efficiently store tuple references (Masahiko Sawada, John Naylor) § § § §
Additionally, vacuum is no longer silently limited to one gigabyte of memory when maintenance_work_mem or autovacuum_work_mem are higher.
Optimize vacuuming of relations with no indexes (Melanie Plageman) §
Increase default vacuum_buffer_usage_limit to 2MB (Thomas Munro) §
Improve performance when checking roles with many memberships (Nathan Bossart) §
Improve performance of heavily-contended WAL writes (Bharath Rupireddy) §
Improve performance when transferring large blocks of data to a client (Melih Mutlu) §
Allow the grouping of file system reads with the new system variable io_combine_limit (Thomas Munro, Andres Freund, Melanie Plageman, Nazir Bilal Yavuz) § § §
       Create system view pg_stat_checkpointer
       (Bharath Rupireddy, Anton A. Melnikov, Alexander Korotkov)
       §
       §
       §
       
       Relevant columns have been removed from pg_stat_bgwriter
       and added to this new system view.
       
Improve control over resetting statistics (Atsushi Torikoshi, Bharath Rupireddy) § § §
       Allow pg_stat_reset_shared()
       (with no arguments) and
       pg_stat_reset_shared(NULL) to reset all
       shared statistics.  Allow pg_stat_reset_shared('slru') and pg_stat_reset_slru()
       (with no arguments) to reset SLRU statistics,
       which was already possible with pg_stat_reset_slru(NULL).
       
Add log messages related to WAL recovery from backups (Andres Freund) §
       Add log_connections log line for
       trust connections (Jacob Champion)
       §
       
Add log message to report walsender acquisition and release of replication slots (Bharath Rupireddy) §
This is enabled by the server variable log_replication_commands.
       Add system view pg_wait_events
       that reports wait event types (Bertrand Drouvot)
       §
       
       This is useful for adding descriptions
       to wait events reported in pg_stat_activity.
       
Add wait events for checkpoint delays (Thomas Munro) §
Allow vacuum to report the progress of index processing (Sami Imseih) §
       This appears in system view pg_stat_progress_vacuum
       columns indexes_total and
       indexes_processed.
       
Allow granting the right to perform maintenance operations (Nathan Bossart) §
       The permission can be granted on a per-table basis using the MAINTAIN
       privilege and on a per-role basis via the pg_maintain
       predefined role.  Permitted operations are
       VACUUM, ANALYZE,
       REINDEX, REFRESH MATERIALIZED
       VIEW, CLUSTER, and LOCK
       TABLE.
       
       Allow roles with pg_monitor
       membership to execute pg_current_logfile()
       (Pavlo Golub, Nathan Bossart)
       §
       
       Add system variable allow_alter_system
       to disallow ALTER
       SYSTEM (Jelte Fennema-Nio, Gabriele Bartolini)
       §
       
       Allow ALTER
       SYSTEM to set unrecognized custom server variables
       (Tom Lane)
       §
       
       This is also possible with GRANT
       ON PARAMETER.
       
Add server variable transaction_timeout to restrict the duration of transactions (Andrey Borodin, Japin Li, Junwang Zhao, Alexander Korotkov) § § §
Add a builtin platform-independent collation provider (Jeff Davis) § § § §
       This supports C and C.UTF-8
       collations.
       
Add server variable huge_pages_status to report the use of huge pages by Postgres (Justin Pryzby) §
       This is useful when huge_pages is set to
       try.
       
Add server variable to disable event triggers (Daniel Gustafsson) §
The setting, event_triggers, allows for the temporary disabling of event triggers for debugging.
Allow the SLRU cache sizes to be configured (Andrey Borodin, Dilip Kumar, Alvaro Herrera) §
The new server variables are commit_timestamp_buffers, multixact_member_buffers, multixact_offset_buffers, notify_buffers, serializable_buffers, subtransaction_buffers, and transaction_buffers. commit_timestamp_buffers, transaction_buffers, and subtransaction_buffers scale up automatically with shared_buffers.
Add support for incremental file system backup (Robert Haas, Jakub Wartak, Tomas Vondra) § §
       Incremental backups can be created using pg_basebackup's
       new --incremental
       option.  The new application pg_combinebackup
       allows manipulation of base and incremental file system backups.
       
Allow the creation of WAL summarization files (Robert Haas, Nathan Bossart, Hubert Depesz Lubaczewski) § § § §
       These files record the block numbers that have changed within an
       LSN
       range and are useful for incremental file
       system backups.  This is controlled by the server
       variables summarize_wal and wal_summary_keep_time, and introspected with pg_available_wal_summaries(),
       pg_wal_summary_contents(), and
       pg_get_wal_summarizer_state().
       
Add the system identifier to file system backup manifest files (Amul Sul) §
This helps detect invalid WAL usage.
       Allow connection string value
       dbname to be written when pg_basebackup
       writes connection information to
       postgresql.auto.conf (Vignesh C, Hayato Kuroda)
       §
       
       Add column pg_replication_slots.invalidation_reason
       to report the reason for invalid slots (Shveta Malik, Bharath
       Rupireddy)
       §
       §
       
       Add column pg_replication_slots.inactive_since
       to report slot inactivity duration (Bharath Rupireddy)
       §
       §
       §
       
       Add function pg_sync_replication_slots()
       to synchronize logical replication slots (Hou Zhijie, Shveta Malik,
       Ajin Cherian, Peter Eisentraut)
       §
       §
       
       Add the failover property to the replication protocol (Hou
       Zhijie, Shveta Malik)
       §
       
Add application pg_createsubscriber to create a logical replica from a physical standby server (Euler Taveira) §
Have pg_upgrade migrate valid logical slots and subscriptions (Hayato Kuroda, Hou Zhijie, Vignesh C, Julien Rouhaud, Shlok Kyal) § §
This allows logical replication to continue quickly after the upgrade. This only works for old PostgreSQL clusters that are version 17 or later.
Enable the failover of logical slots (Hou Zhijie, Shveta Malik, Ajin Cherian) §
       This is controlled by an optional fifth argument to pg_create_logical_replication_slot().
       
Add server variable sync_replication_slots to enable failover logical slot synchronization (Shveta Malik, Hou Zhijie, Peter Smith) § §
       Add logical replication failover control to CREATE/ALTER
       SUBSCRIPTION (Shveta Malik, Hou Zhijie, Ajin
       Cherian)
       §
       §
       
Allow the application of logical replication changes to use hash indexes on the subscriber (Hayato Kuroda) §
Previously only btree indexes could be used for this purpose.
Improve logical decoding performance in cases where there are many subtransactions (Masahiko Sawada) §
Restart apply workers if subscription owner's superuser privileges are revoked (Vignesh C) §
This forces reauthentication.
       Add flush option to pg_logical_emit_message()
       (Michael Paquier)
       §
       
This makes the message durable.
Allow specification of physical standbys that must be synchronized before they are visible to subscribers (Hou Zhijie, Shveta Malik) § §
The new server variable is synchronized_standby_slots.
       Add worker type column to pg_stat_subscription
       (Peter Smith)
       §
       
      Add new COPY
      option ON_ERROR ignore to discard error rows
      (Damir Belyalov, Atsushi Torikoshi, Alex Shulgin, Jian He, Yugo
      Nagata)
      §
      §
      §
      §
      
      The default behavior is ON_ERROR stop.
      
      Add new COPY option
      LOG_VERBOSITY which reports COPY
      FROM ignored error rows (Bharath Rupireddy)
      §
      
      Allow COPY FROM to report the number of skipped
      rows during processing (Atsushi Torikoshi)
      §
      
      This appears in system view column pg_stat_progress_copy.tuples_skipped.
      
      In COPY FROM, allow easy specification that all
      columns should be forced null or not null (Zhang Mingli)
      §
      
Allow partitioned tables to have identity columns (Ashutosh Bapat) §
Allow exclusion constraints on partitioned tables (Paul A. Jungwirth) §
As long as exclusion constraints compare partition key columns for equality, other columns can use exclusion constraint-specific comparisons.
      Add clearer ALTER
      TABLE method to set a column to the default
      statistics target (Peter Eisentraut)
      §
      
      The new syntax is ALTER TABLE ... SET STATISTICS
      DEFAULT; using SET STATISTICS -1
      is still supported.
      
      Allow ALTER TABLE to change a column's generation
      expression (Amul Sul)
      §
      
      The syntax is ALTER TABLE ... ALTER COLUMN ... SET
      EXPRESSION.
      
Allow specification of table access methods on partitioned tables (Justin Pryzby, Soumyadeep Chakraborty, Michael Paquier) § §
      Add DEFAULT setting for ALTER TABLE
      .. SET ACCESS METHOD (Michael Paquier)
      §
      
Add support for event triggers that fire at connection time (Konstantin Knizhnik, Mikhail Gribkov) §
      Add event trigger support for REINDEX (Garrett
      Thornburg, Jian He)
      §
      
      Allow parenthesized syntax for CLUSTER options if
      a table name is not specified (Nathan Bossart)
      §
      
       Allow EXPLAIN to report
       optimizer memory usage (Ashutosh Bapat)
       §
       
       The option is called MEMORY.
       
       Add EXPLAIN option SERIALIZE
       to report the cost of converting data for network transmission
       (Stepan Rutz, Matthias van de Meent)
       §
       
       Add local I/O block read/write timing statistics to
       EXPLAIN's BUFFERS output
       (Nazir Bilal Yavuz)
       §
       
       Improve EXPLAIN's display of SubPlan nodes and
       output parameters (Tom Lane, Dean Rasheed)
       §
       
       Add JIT deform_counter
       details to EXPLAIN (Dmitry Dolgov)
       §
       
      Allow the interval data type to support
      +/-infinity values (Joseph Koshakow, Jian He,
      Ashutosh Bapat)
      §
      
      Allow the use of an ENUM added via ALTER TYPE if
      the type was created in the same transaction (Tom Lane)
      §
      
This was previously disallowed.
      Allow MERGE to modify updatable views (Dean
      Rasheed)
      §
      
      Add WHEN NOT MATCHED BY SOURCE to
      MERGE (Dean Rasheed)
      §
      
      WHEN NOT MATCHED on target rows was already
      supported.
      
      Allow MERGE to use the
      RETURNING clause (Dean Rasheed)
      §
      
      The new RETURNING function
      merge_action() reports on the
      DML that generated the row.
      
      Add function JSON_TABLE()
      to convert JSON data to a table representation (Nikita
      Glukhov, Teodor Sigaev, Oleg Bartunov, Alexander Korotkov, Andrew
      Dunstan, Amit Langote, Jian He)
      §
      §
      
      This function can be used in the FROM clause of
      SELECT queries as a tuple source.
      
      Add SQL/JSON constructor functions JSON(),
      JSON_SCALAR(), and
      JSON_SERIALIZE() (Nikita Glukhov, Teodor Sigaev,
      Oleg Bartunov, Alexander Korotkov, Andrew Dunstan, Amit Langote)
      §
      
      Add SQL/JSON query functions JSON_EXISTS(),
      JSON_QUERY(), and
      JSON_VALUE() (Nikita Glukhov, Teodor Sigaev,
      Oleg Bartunov, Alexander Korotkov, Andrew Dunstan, Amit Langote,
      Peter Eisentraut, Jian He)
      §
      §
      §
      §
      §
      
      Add jsonpath
      methods to convert JSON values to other
      JSON data types (Jeevan Chalke)
      §
      
      The jsonpath methods are .bigint(),
      .boolean(), .date(),
      .decimal([precision [, scale]]),
      .integer(), .number(),
      .string(), .time(),
      .time_tz(), .timestamp(),
      and .timestamp_tz().
      
      Add to_timestamp()
      time zone format specifiers (Tom Lane)
      §
      
      TZ accepts time zone abbreviations or numeric
      offsets, while OF accepts only numeric offsets.
      
      Allow the session time zone
      to be specified by AT LOCAL (Vik Fearing)
      §
      
This is useful when converting adding and removing time zones from time stamps values, rather than specifying the literal session time zone.
      Add functions uuid_extract_timestamp()
      and uuid_extract_version() to return
      UUID information (Andrey Borodin)
      §
      
Add functions to generate random numbers in a specified range (Dean Rasheed) §
      The functions are random(min,
      max) and they take values of type
      integer, bigint, and numeric.
      
Add functions to convert integers to binary and octal strings (Eric Radman, Nathan Bossart) §
      The functions are to_bin()
      and to_oct().
      
Add Unicode informational functions (Jeff Davis) §
      Function unicode_version()
      returns the Unicode version,
      icu_unicode_version()
      returns the ICU version, and
      unicode_assigned() returns if the characters
      are assigned Unicode codepoints.
      
      Add function xmltext()
      to convert text to a single XML text node (Jim Jones)
      §
      
      Add function to_regtypemod()
      to return the type modifier of a type specification (David Wheeler,
      Erik Wienhold)
      §
      
      Add pg_basetype()
      function to return a domain's base type (Steve Chavez)
      §
      
      Add function pg_column_toast_chunk_id()
      to return a value's TOAST identifier
      (Yugo Nagata)
      §
      
      This returns NULL if the value is not stored
      in TOAST.
      
Add libpq function to change role passwords (Joe Conway) §
      The new function, PQchangePassword(),
      hashes the new password before sending it to the server.
      
Add libpq functions to close portals and prepared statements (Jelte Fennema-Nio) §
      The functions are PQclosePrepared(),
      PQclosePortal(),
      PQsendClosePrepared(),
      and PQsendClosePortal().
      
Add libpq API which allows for blocking and non-blocking cancel requests, with encryption if already in use (Jelte Fennema-Nio) §
Previously only blocking, unencrypted cancel requests were supported.
      Add libpq function PQsocketPoll()
      to allow polling of network sockets (Tristan Partin, Tom Lane)
      §
      §
      
      Add libpq function PQsendPipelineSync()
      to send a pipeline synchronization point (Anton Kirilov)
      §
      
      This is similar to PQpipelineSync()
      but it does not flush to the server unless the size threshold of
      the output buffer is reached.
      
      Add libpq function PQsetChunkedRowsMode()
      to allow retrieval of results in chunks (Daniel Vérité)
      §
      
Allow TLS connections without requiring a network round-trip negotiation (Greg Stark, Heikki Linnakangas, Peter Eisentraut, Michael Paquier, Daniel Gustafsson) § § § § § § § §
      This is enabled with the client-side option sslnegotiation=direct,
      requires ALPN, and only works on
      PostgreSQL 17 and later servers.
      
Improve psql display of default and empty privileges (Erik Wienhold, Laurenz Albe) §
      Command \dp now displays (none)
      for empty privileges;  default still displays as empty.
      
      Have backslash commands honor \pset null (Erik
      Wienhold, Laurenz Albe)
      §
      
      Previously \pset null was ignored.
      
      Allow psql's \watch
      to stop after a minimum number of rows returned (Greg Sabino Mullane)
      §
      
      The parameter is min_rows.
      
Allow psql connection attempts to be canceled with control-C (Tristan Partin) §
      Allow psql to honor
      FETCH_COUNT for non-SELECT
      queries (Daniel Vérité)
      §
      
Improve psql tab completion (Dagfinn Ilmari Mannsåker, Gilles Darold, Christoph Heiss, Steve Chavez, Vignesh C, Pavel Borisov, Jian He) § § § § § § § §
Add application pg_walsummary to dump WAL summary files (Robert Haas) §
Allow pg_dump's large objects to be restorable in batches (Tom Lane) §
This allows the restoration of many large objects to avoid transaction limits and to be restored in parallel.
      Add pg_dump option
      --exclude-extension (Ayush Vatsa)
      §
      
Allow pg_dump, pg_dumpall, and pg_restore to specify include/exclude objects in a file (Pavel Stehule, Daniel Gustafsson) §
      The option is called --filter.
      
      Add the --sync-method parameter to several client
      applications (Justin Pryzby, Nathan Bossart)
      §
      
The applications are initdb, pg_basebackup, pg_checksums, pg_dump, pg_rewind, and pg_upgrade.
      Add pg_restore
      option --transaction-size to allow object restores
      in transaction batches (Tom Lane)
      §
      
This allows the performance benefits of transaction batches without the problems of excessively large transaction blocks.
      Change pgbench debug
      mode option from -d to --debug
      (Greg Sabino Mullane)
      §
      
      Option -d is now used for the database name,
      and the new --dbname option can be used as well.
      
      Add pgbench option --exit-on-abort to exit after
      any client aborts (Yugo Nagata)
      §
      
      Add pgbench command \syncpipeline to allow
      sending of sync messages (Anthonin Bonnefoy)
      §
      
Allow pg_archivecleanup to remove backup history files (Atsushi Torikoshi) §
      The option is --clean-backup-history.
      
Add some long options to pg_archivecleanup (Atsushi Torikoshi) §
      The long options are --debug,
      --dry-run, and --strip-extension.
      
Allow pg_basebackup and pg_receivewal to use dbname in their connection specification (Jelte Fennema-Nio) §
This is useful for connection poolers that are sensitive to the database name.
      Add pg_upgrade
      option --copy-file-range (Thomas Munro)
      §
      
This is supported on Linux and FreeBSD.
      Allow reindexdb
      --index to process indexes from different tables
      in parallel (Maxim Orlov, Svetlana Derevyanko, Alexander Korotkov)
      §
      
Allow reindexdb, vacuumdb, and clusterdb to process objects in all databases matching a pattern (Nathan Bossart) § § §
      The new option --all controls this behavior.
      
Remove support for OpenSSL 1.0.1 (Michael Paquier) §
Allow tests to pass in OpenSSL FIPS mode (Peter Eisentraut) § §
Use CPU AVX-512 instructions for bit counting (Paul Amonson, Nathan Bossart, Ants Aasma) § §
Require LLVM version 10 or later (Thomas Munro) §
Use native CRC instructions on 64-bit LoongArch CPUs (Xudong Yang) §
Remove AIX support (Heikki Linnakangas) §
Remove the Microsoft Visual Studio-specific PostgreSQL build option (Michael Paquier) §
Meson is now the only available method for Visual Studio builds.
      Remove configure option --disable-thread-safety
      (Thomas Munro, Heikki Linnakangas)
      §
      §
      
We now assume all supported platforms have sufficient thread support.
      Remove configure option
      --with-CC (Heikki Linnakangas)
      §
      
      Setting the CC environment variable is now the only
      supported method for specifying the compiler.
      
User-defined data type receive functions will no longer receive their data null-terminated (David Rowley) §
      Add incremental JSON parser for use with huge
      JSON documents (Andrew Dunstan)
      §
      
      Convert top-level README file to
      Markdown (Nathan Bossart)
      §
      
      Remove no longer needed top-level INSTALL file
      (Tom Lane)
      §
      
      Remove make's distprep
      option (Peter Eisentraut)
      §
      
Add make support for Android shared libraries (Peter Eisentraut) §
Add backend support for injection points (Michael Paquier) § § § §
This is used for server debugging and they must be enabled at server compile time.
Add dynamic shared memory registry (Nathan Bossart) §
This allows shared libraries which are not initialized at startup to coordinate dynamic shared memory access.
      Fix emit_log_hook to use the same time value as
      other log records for the same query (Kambam Vinay, Michael Paquier)
      §
      
      Improve documentation for using jsonpath for
      predicate checks (David Wheeler)
      §
      
Allow joins with non-join qualifications to be pushed down to foreign servers and custom scans (Richard Guo, Etsuro Fujita) §
Foreign data wrappers and custom scans will need to be modified to handle these cases.
      Allow pushdown of EXISTS and IN
      subqueries to postgres_fdw foreign servers
      (Alexander Pyhalov)
      §
      
Increase the default foreign data wrapper tuple cost (David Rowley, Umair Shahid) § §
This value is used by the optimizer.
Allow dblink database operations to be interrupted (Noah Misch) §
Allow the creation of hash indexes on ltree columns (Tommy Pavlicek) §
This also enables hash join and hash aggregation on ltree columns.
Allow unaccent character translation rules to contain whitespace and quotes (Michael Paquier) §
      The syntax for the unaccent.rules file has
      changed.
      
      Allow amcheck
      to check for unique constraint violations using new option
      --checkunique (Anastasia Lubennikova, Pavel Borisov,
      Maxim Orlov)
      §
      
Allow citext tests to pass in OpenSSL FIPS mode (Peter Eisentraut) §
Allow pgcrypto tests to pass in OpenSSL FIPS mode (Peter Eisentraut) §
      Allow ALTER
      OPERATOR to set more optimization attributes
      (Tommy Pavlicek)
      §
      
This is useful for extensions.
Allow extensions to define custom wait events (Masahiro Ikeda) § § § §
Custom wait events have been added to postgres_fdw and dblink.
      Add pg_buffercache
      function pg_buffercache_evict() to allow shared
      buffer eviction (Palak Chaturvedi, Thomas Munro)
      §
      
This is useful for testing.
       Replace CALL
       parameters in pg_stat_statements with
       placeholders (Sami Imseih)
       §
       
       Replace savepoint names stored in
       pg_stat_statements with placeholders
       (Greg Sabino Mullane)
       §
       
       This greatly reduces the number of entries needed to record SAVEPOINT,
       RELEASE
       SAVEPOINT, and ROLLBACK TO
       SAVEPOINT commands.
       
       Replace the two-phase commit GIDs stored in
       pg_stat_statements with placeholders
       (Michael Paquier)
       §
       
       This greatly reduces the number of entries needed to record
       PREPARE
       TRANSACTION, COMMIT
       PREPARED, and ROLLBACK
       PREPARED.
       
       Track DEALLOCATE
       in pg_stat_statements (Dagfinn Ilmari
       Mannsåker, Michael Paquier)
       §
       
       DEALLOCATE names are stored in
       pg_stat_statements as placeholders.
       
       Add local I/O block read/write timing statistics columns of
       pg_stat_statements (Nazir Bilal Yavuz)
       §
       §
       
       The new columns are local_blk_read_time
       and local_blk_write_time.
       
       Add JIT deform_counter details to
       pg_stat_statements (Dmitry Dolgov)
       §
       
       Add optional fourth argument (minmax_only)
       to pg_stat_statements_reset() to allow for
       the resetting of only min/max statistics (Andrei Zubkov)
       §
       
       This argument defaults to false.
       
       Add pg_stat_statements
       columns stats_since and
       minmax_stats_since to track entry
       creation time and last min/max reset time (Andrei Zubkov)
       §
       
The following individuals (in alphabetical order) have contributed to this release as patch authors, committers, reviewers, testers, or reporters of issues.
| Abhijit Menon-Sen | 
| Adnan Dautovic | 
| Aidar Imamov | 
| Ajin Cherian | 
| Akash Shankaran | 
| Akshat Jaimini | 
| Alaa Attya | 
| Aleksander Alekseev | 
| Aleksej Orlov | 
| Alena Rybakina | 
| Alex Hsieh | 
| Alex Malek | 
| Alex Shulgin | 
| Alex Work | 
| Alexander Korotkov | 
| Alexander Kozhemyakin | 
| Alexander Kuzmenkov | 
| Alexander Lakhin | 
| Alexander Pyhalov | 
| Alexey Palazhchenko | 
| Alfons Kemper | 
| Álvaro Herrera | 
| Amadeo Gallardo | 
| Amit Kapila | 
| Amit Langote | 
| Amul Sul | 
| Anastasia Lubennikova | 
| Anatoly Zaretsky | 
| Andreas Karlsson | 
| Andreas Ulbrich | 
| Andrei Lepikhov | 
| Andrei Zubkov | 
| Andres Freund | 
| Andrew Alsup | 
| Andrew Atkinson | 
| Andrew Bille | 
| Andrew Dunstan | 
| Andrew Kane | 
| Andrey Borodin | 
| Andrey Rachitskiy | 
| Andrey Sokolov | 
| Andy Fan | 
| Anthonin Bonnefoy | 
| Anthony Hsu | 
| Anton Kirilov | 
| Anton Melnikov | 
| Anton Voloshin | 
| Antonin Houska | 
| Ants Aasma | 
| Antti Lampinen | 
| Aramaki Zyake | 
| Artem Anisimov | 
| Artur Zakirov | 
| Ashutosh Bapat | 
| Ashutosh Sharma | 
| Atsushi Torikoshi | 
| Attila Gulyás | 
| Ayush Tiwari | 
| Ayush Vatsa | 
| Bartosz Chrol | 
| Benoît Ryder | 
| Bernd Helmle | 
| Bertrand Drouvot | 
| Bharath Rupireddy | 
| Bo Andreson | 
| Boshomi Phenix | 
| Bowen Shi | 
| Boyu Yang | 
| Bruce Momjian | 
| Cameron Vogt | 
| Cary Huang | 
| Cédric Villemain | 
| Changhong Fei | 
| Chantal Keller | 
| Chapman Flack | 
| Chengxi Sun | 
| Chris Travers | 
| Christian Maurer | 
| Christian Stork | 
| Christoph Berg | 
| Christoph Heiss | 
| Christophe Courtois | 
| Christopher Kline | 
| Claudio Freire | 
| Colin Caine | 
| Corey Huinker | 
| Curt Kolovson | 
| Dag Lem | 
| Dagfinn Ilmari Mannsåker | 
| Damir Belyalov | 
| Daniel Fredouille | 
| Daniel Gustafsson | 
| Daniel Shelepanov | 
| Daniel Vérité | 
| Daniel Westermann | 
| Darren Rush | 
| Dave Cramer | 
| Dave Page | 
| David Christensen | 
| David Cook | 
| David G. Johnston | 
| David Geier | 
| David Hillman | 
| David Perez | 
| David Rowley | 
| David Steele | 
| David Wheeler | 
| David Zhang | 
| Dean Rasheed | 
| Denis Erokhin | 
| Denis Laxalde | 
| Devrim Gündüz | 
| Dilip Kumar | 
| Dimitrios Apostolou | 
| Dmitry Dolgov | 
| Dmitry Koval | 
| Dmitry Vasiliev | 
| Dominique Devienne | 
| Dong Wook Lee | 
| Donghang Lin | 
| Dongming Liu | 
| Drew Callahan | 
| Drew Kimball | 
| Dzmitry Jachnik | 
| Egor Chindyaskin | 
| Egor Rogov | 
| Ekaterina Kiryanova | 
| Elena Indrupskaya | 
| Elizabeth Christensen | 
| Emre Hasegeli | 
| Eric Cyr | 
| Eric Mutta | 
| Eric Radman | 
| Eric Ridge | 
| Erik Rijkers | 
| Erik Wienhold | 
| Erki Eessaar | 
| Ethan Mertz | 
| Etsuro Fujita | 
| Eugen Konkov | 
| Euler Taveira | 
| Evan Macbeth | 
| Evgeny Morozov | 
| Fabien Coelho | 
| Fabrízio de Royes Mello | 
| Farias de Oliveira | 
| Feliphe Pozzer | 
| Fire Emerald | 
| Flavien Guedez | 
| Floris Van Nee | 
| Francesco Degrassi | 
| Frank Streitzig | 
| Gabriele Bartolini | 
| Garrett Thornburg | 
| Gavin Flower | 
| Gavin Panella | 
| Gilles Darold | 
| Gilles Parc | 
| Grant Gryczan | 
| Greg Nancarrow | 
| Greg Sabino Mullane | 
| Greg Stark | 
| Gurjeet Singh | 
| Haiying Tang | 
| Hajime Matsunaga | 
| Hal Takahara | 
| Hanefi Onaldi | 
| Hannu Krosing | 
| Hans Buschmann | 
| Hao Wu | 
| Hao Zhang | 
| Hayato Kuroda | 
| Heikki Linnakangas | 
| Hemanth Sandrana | 
| Himanshu Upadhyaya | 
| Hironobu Suzuki | 
| Holger Reise | 
| Hongxu Ma | 
| Hongyu Song | 
| Horst Reiterer | 
| Hubert Lubaczewski | 
| Hywel Carver | 
| Ian Barwick | 
| Ian Ilyasov | 
| Ilya Nenashev | 
| Isaac Morland | 
| Israel Barth Rubio | 
| Ivan Kartyshov | 
| Ivan Kolombet | 
| Ivan Lazarev | 
| Ivan Panchenko | 
| Ivan Trofimov | 
| Jacob Champion | 
| Jacob Speidel | 
| Jacques Combrink | 
| Jaime Casanova | 
| Jakub Wartak | 
| James Coleman | 
| James Pang | 
| Jani Rahkola | 
| Japin Li | 
| Jeevan Chalke | 
| Jeff Davis | 
| Jeff Janes | 
| Jelte Fennema-Nio | 
| Jeremy Schneider | 
| Jian Guo | 
| Jian He | 
| Jim Jones | 
| Jim Keener | 
| Jim Nasby | 
| Jingtang Zhang | 
| Jingxian Li | 
| Jingzhou Fu | 
| Joe Conway | 
| Joel Jacobson | 
| John Ekins | 
| John Hsu | 
| John Morris | 
| John Naylor | 
| John Russell | 
| Jonathan Katz | 
| Jordi Gutiérrez | 
| Joseph Koshakow | 
| Josh Kupershmidt | 
| Joshua D. Drake | 
| Joshua Uyehara | 
| Jubilee Young | 
| Julien Rouhaud | 
| Junwang Zhao | 
| Justin Pryzby | 
| Kaido Vaikla | 
| Kambam Vinay | 
| Karen Talarico | 
| Karina Litskevich | 
| Karl O. Pinc | 
| Kashif Zeeshan | 
| Kim Johan Andersson | 
| Kirill Reshke | 
| Kirk Parker | 
| Kirk Wolak | 
| Kisoon Kwon | 
| Koen De Groote | 
| Kohei KaiGai | 
| Kong Man | 
| Konstantin Knizhnik | 
| Kouhei Sutou | 
| Krishnakumar R | 
| Kuntal Ghosh | 
| Kurt Roeckx | 
| Kyotaro Horiguchi | 
| Lang Liu | 
| Lars Kanis | 
| Laurenz Albe | 
| Lauri Laanmets | 
| Legs Mansion | 
| Lukas Fittl | 
| Magnus Hagander | 
| Mahendrakar Srinivasarao | 
| Maiquel Grassi | 
| Manos Emmanouilidis | 
| Marcel Hofstetter | 
| Marcos Pegoraro | 
| Marian Krucina | 
| Marina Polyakova | 
| Mark Dilger | 
| Mark Guertin | 
| Mark Sloan | 
| Markus Winand | 
| Marlene Reiterer | 
| Martín Marqués | 
| Martin Nash | 
| Martin Schlossarek | 
| Masahiko Sawada | 
| Masahiro Ikeda | 
| Masaki Kuwamura | 
| Masao Fujii | 
| Mason Sharp | 
| Matheus Alcantara | 
| Mats Kindahl | 
| Matthias Kuhn | 
| Matthias van de Meent | 
| Maxim Boguk | 
| Maxim Orlov | 
| Maxim Yablokov | 
| Maxime Boyer | 
| Melanie Plageman | 
| Melih Mutlu | 
| Merlin Moncure | 
| Micah Gate | 
| Michael Banck | 
| Michael Bondarenko | 
| Michael Paquier | 
| Michael Wang | 
| Michael Zhilin | 
| Michail Nikolaev | 
| Michal Bartak | 
| Michal Kleczek | 
| Mikhail Gribkov | 
| Mingli Zhang | 
| Miroslav Bendik | 
| Mitsuru Hinata | 
| Moaaz Assali | 
| Muralikrishna Bandaru | 
| Nathan Bossart | 
| Nazir Bilal Yavuz | 
| Neil Tiffin | 
| Ngigi Waithaka | 
| Nikhil Benesch | 
| Nikhil Raj | 
| Nikita Glukhov | 
| Nikita Kalinin | 
| Nikita Malakhov | 
| Nikolay Samokhvalov | 
| Nikolay Shaplov | 
| Nisha Moond | 
| Nishant Sharma | 
| Nitin Jadhav | 
| Noah Misch | 
| Noriyoshi Shinoda | 
| Ole Peder Brandtzæg | 
| Oleg Bartunov | 
| Oleg Sibiryakov | 
| Oleg Tselebrovskiy | 
| Olleg Samoylov | 
| Onder Kalaci | 
| Ondrej Navratil | 
| Pablo Kharo | 
| Palak Chaturvedi | 
| Pantelis Theodosiou | 
| Paul Amonson | 
| Paul Jungwirth | 
| Pavel Borisov | 
| Pavel Kulakov | 
| Pavel Luzanov | 
| Pavel Stehule | 
| Pavlo Golub | 
| Pedro Gallegos | 
| Pete Storer | 
| Peter Eisentraut | 
| Peter Geoghegan | 
| Peter Smith | 
| Philip Warner | 
| Philipp Salvisberg | 
| Pierre Ducroquet | 
| Pierre Fortin | 
| Przemyslaw Sztoch | 
| Quynh Tran | 
| Raghuveer Devulapalli | 
| Ranier Vilela | 
| Reid Thompson | 
| Rian McGuire | 
| Richard Guo | 
| Richard Vesely | 
| Ridvan Korkmaz | 
| Robert Haas | 
| Robert Scott | 
| Robert Treat | 
| Roberto Mello | 
| Robins Tharakan | 
| Roman Lozko | 
| Ronan Dunklau | 
| Rui Zhao | 
| Ryo Matsumura | 
| Ryoga Yoshida | 
| Sameer Kumar | 
| Sami Imseih | 
| Samuel Dussault | 
| Sanjay Minni | 
| Satoru Koizumi | 
| Sebastian Skalacki | 
| Sergei Glukhov | 
| Sergei Kornilov | 
| Sergey Prokhorenko | 
| Sergey Sargsyan | 
| Sergey Shinderuk | 
| Shaozhong Shi | 
| Shaun Thomas | 
| Shay Rojansky | 
| Shihao Zhong | 
| Shinya Kato | 
| Shlok Kyal | 
| Shruthi Gowda | 
| Shubham Khanna | 
| Shulin Zhou | 
| Shveta Malik | 
| Simon Riggs | 
| Soumyadeep Chakraborty | 
| Sravan Velagandula | 
| Stan Hu | 
| Stepan Neretin | 
| Stepan Rutz | 
| Stéphane Schildknecht | 
| Stephane Tachoires | 
| Stephen Frost | 
| Steve Atkins | 
| Steve Chavez | 
| Suraj Khamkar | 
| Suraj Kharage | 
| Svante Richter | 
| Svetlana Derevyanko | 
| Sylvain Frandaz | 
| Takayuki Tsunakawa | 
| Tatsuo Ishii | 
| Tatsuro Yamada | 
| Tender Wang | 
| Teodor Sigaev | 
| Thom Brown | 
| Thomas Munro | 
| Tim Carey-Smith | 
| Tim Needham | 
| Tim Palmer | 
| Tobias Bussmann | 
| Tom Lane | 
| Tomas Vondra | 
| Tommy Pavlicek | 
| Tomonari Katsumata | 
| Tristan Partin | 
| Tristen Raab | 
| Tung Nguyen | 
| Umair Shahid | 
| Uwe Binder | 
| Valerie Woolard | 
| Vallimaharajan G | 
| Vasya Boytsov | 
| Victor Wagner | 
| Victor Yegorov | 
| Victoria Shepard | 
| Vidushi Gupta | 
| Vignesh C | 
| Vik Fearing | 
| Viktor Leis | 
| Vinayak Pokale | 
| Vitaly Burovoy | 
| Vojtech Benes | 
| Wei Sun | 
| Wei Wang | 
| Wenjiang Zhang | 
| Will Mortensen | 
| Willi Mann | 
| Wolfgang Walther | 
| Xiang Liu | 
| Xiaoran Wang | 
| Xing Guo | 
| Xudong Yang | 
| Yahor Yuzefovich | 
| Yajun Hu | 
| Yaroslav Saburov | 
| Yong Li | 
| Yongtao Huang | 
| Yugo Nagata | 
| Yuhang Qiu | 
| Yuki Seino | 
| Yura Sokolov | 
| Yurii Rashkovskii | 
| Yuuki Fujii | 
| Yuya Watari | 
| Yves Colin | 
| Zhihong Yu | 
| Zhijie Hou | 
| Zongliang Quan | 
| Zubeyr Eryilmaz | 
| Zuming Jiang |