#PostgreSQL

We’re continuing our review of the March CommitFest for PostgreSQL 19. This third article in the series covers the changes related to our DBA3 and DBS courses. As a reminder, here’s the plan for our coverage of the final PostgreSQL 19 CommitFest: Part 5.1 (QPT) Part 5.2 (DBA1, DBA2) Part 5.3 (DBA3, DBS) -- you are here 🙂 Part 5.4 (SQL, DEV1, DEV2) For the earlier CommitFests, see: 2025-07 , 2025-09 , 2025-11 , 2026-01 . Here’s what’s covered: pg_verifybackup, pg_waldump: reading WAL from tar archives pg_stat_recovery: monitoring replication and recovery psql: replica indicator in the prompt pg_createsubscriber --logdir: writing diagnostics to files Publications: excluding specific tables Logical replication subscriptions: connecting via postgres_fdw wal_sender_shutdown_timeout: limiting the wait for WAL replication at shutdown wal_receiver_timeout: per-user and per-subscription settings SSL: server-side SNI GRANT/REVOKE … GRANTED BY Password expiration warning MD5 passwords: more end-of-support preparations pg_[read|write]_all_data: now for large objects too psql: comments for publications, subscriptions, and extended statistics ...

We’re continuing our review of the March CommitFest for PostgreSQL 19. This second article in the series covers the changes related to our DBA1 and DBA2 courses. As a reminder, here’s the plan for our coverage of the final PostgreSQL 19 CommitFest: Part 5.1 (QPT) Part 5.2 (DBA1, DBA2) -- you are here 🙂 Part 5.3 (DBA3, DBS) Part 5.4 (SQL, DEV1, DEV2) For the earlier CommitFests, see: 2025-07 , 2025-09 , 2025-11 , 2026-01 . Here’s what’s covered: REPACK: rewriting a table to reclaim disk space Autovacuum: table processing order Autovacuum: parallel index vacuuming Enhanced transaction ID wraparound warnings Checkpoint reason in the completion log message Less WAL and on-access visibility map updates More code paths use read streams pg_stat_lock: statistics on long lock waits pg_upgrade: faster large object transfer, part 2 oid2name: file paths relative to PGDATA psql: comments on internal queries log_min_messages per backend type Stats reset time for pg_stat_database_conflicts and pg_statio_all_sequences ...

We’re wrapping up our series of articles reviewing the changes in PostgreSQL 19. The previous articles covered the first four CommitFests: 2025-07 , 2025-09 , 2025-11 , 2026-01 . Today we begin our review of the March 2026 CommitFest . Why «begin»? As in previous years, the March review is going to be a long one: the final CommitFest of the cycle is where many of the most important changes land. Such a review is hard not only to write but also to read all the way through 🙂. That’s why this time it’s split into four articles. The first article covers everything related to query optimization, in other words, the topics of our QPT training course. The second will focus on changes more relevant to the DBA1 and DBA2 courses. The third will cover DBA3 and DBS . The fourth will look at new SQL features, as well as changes related to the DEV1 and DEV2 courses. RevertFest But first, let’s look at what won’t make it into version 19. An impressive number of features were committed to version 19 before the feature freeze, only to be reverted before the release: Partitioning: merging and splitting partitions ( 3e8bcc864 ) GROUP BY ALL ( a32733d8f10 ) pg_dumpall: support for all pg_dump output formats ( 7ca548f23a6 ) SQL Property Graph Queries (SQL/PGQ) ( b1f106c80 ) SQL:2011 Application Time Update & Delete ( a4b26b8f7 ) Built-in functions that return the DDL for creating roles , databases , and tablespaces ( db169985c ) Enabling/disabling data checksums without shutting down the cluster ( c05d5ce12 ) At the time of writing, not all open items have been resolved, and the release is tentatively scheduled for October 29. So the list of new features may shrink further. CommitFest With that caveat in mind, let’s move on to the changes related to query optimization. Here’s what’s covered: Query plan stabilization and plan advice auto_explain: logging EXPLAIN options added by extensions EXPLAIN (analyze, timing): reducing timing overhead Planner: IS DISTINCT FROM with non-nullable inputs Planner: cardinality estimation for NOT IN (NULL, …) expressions Planner: anti-join for NOT IN with a subquery Planner: anti-join in queries with a left outer join Extended statistics on virtual generated columns postgres_fdw: importing statistics for foreign tables JIT compilation is disabled by default ...

We’re excited to announce that the DBA2 Configuration and Monitoring of PostgreSQL 16 course has been published in English. The goal of this course is to give you a solid understanding of PostgreSQL’s internal architecture. This knowledge is key to tuning parameters effectively and using monitoring to refine your initial configuration. The course also covers a range of administration topics that go beyond the DBA1 material. All course materials are freely available for self-study. Don’t miss the Student’s Guide—it walks you through setting up the virtual machine and completing the practical tasks. The course was translated by Elena Sharafutdinova, with special thanks to Ilya Bashtanov and Alexander Meleshko for their reviews and help preparing the materials. Some topics from the course are explored in more depth in Egor Rogov’s book PostgreSQL Internals , which is also available as a free ebook on our site. Other courses already available in English include: DBA1 —a beginner-friendly course covering PostgreSQL architecture, installation, server configuration, and management, plus an overview of access control, backup, and replication. DEV1 —a foundational course for backend developers, covering PostgreSQL architecture, basic database objects, server-side programming in SQL and PL/pgSQL, basic data types (including composite types and arrays), and client-side interactions. We’re continuing to translate our courses, which were previously only available to Russian-speaking audiences. More to come—stay tuned.

Continuing the series of CommitFest 19 reviews, today we’re covering the January 2026 CommitFest. The highlights from previous CommitFests are available here: 2025-07 , 2025-09 , 2025-11 . Partitioning: merging and splitting partitions pg_dump[all]/pg_restore: dumping and restoring extended statistics file_fdw: skipping initial rows Logical replication: enabling and disabling WAL logical decoding without server restart Monitoring logical replication slot synchronization delays pg_available_extensions shows extension installation directories New function pg_get_multixact_stats: multixact usage statistics Improvements to vacuum and analyze progress monitoring Vacuum: memory usage information vacuumdb --dry-run jsonb_agg optimization LISTEN/NOTIFY optimization ICU: character conversion function optimization The parameter standard_conforming_strings can no longer be disabled ...

This article reviews the November 2025 CommitFest. For the highlights of the previous two CommitFests, check out our last posts: 2025-07 , 2025-09 . Planner: eager aggregation Converting COUNT(1) and COUNT(not_null_col) to COUNT(*) Parallel TID Range Scan COPY … TO with partitioned tables New function error_on_null Planner support functions for optimizing set-returning functions (SRF) SQL-standard style functions with temporary objects BRIN indexes: using the read stream interface for vacuuming WAIT FOR: waiting for synchronization between replica and primary Logical replication of sequences pg_stat_replication_slots: a counter for memory limit exceeds during logical decoding pg_buffercache: buffer distribution across OS pages pg_buffercache: marking buffers as dirty Statistics reset time for individual relations and functions Monitoring the volume of full page images written to WAL New parameter log_autoanalyze_min_duration psql: search path in the prompt psql: displaying boolean values pg_rewind: skip copying WAL segments already present on the target server pgbench: continue running after SQL command errors ...

The conference gathered about 100 people, including PostgreSQL developers, DBA and customers from all over the world.