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We’re wrapping up our review of the March CommitFest for PostgreSQL 19. This fourth and final article in the series covers the changes related to SQL and to our DEV1 and DEV2 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)

Part 5.4 (SQL, DEV1, DEV2) – you are here 🙂

For the earlier CommitFests, see: 2025-07, 2025-09, 2025-11, 2026-01.

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.

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.

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.

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

Your service has just published a message to RabbitMQ — and then, right at commit time, the database transaction rolls back. The classic distributed-systems nightmare: ghost data, broken consistency, and hours lost to debugging. Usually you fight this with tricky custom code, two-phase commits, or just… crossing your fingers. But what if a PostgreSQL rollback could automatically “roll back” the message too, putting it back into the queue without you writing a single extra line? Here’s how that works.

We continue our series of articles reviewing changes in PostgreSQL 19. This time we'll look at what emerged from the September 2025 CommitFest.

The highlights from the first July CommitFest are available here: 2025-07.

GROUP BY ALL
Window functions: NULL value handling
Event triggers in PL/Python
More precise error message for incorrect routine parameter names
random: random date/time within a specified range
base64url format for encode and decode functions
New debug_print_raw_parse parameter
The log_lock_waits parameter is now enabled by default
pg_stat_progress_basebackup: backup type
vacuumdb: collecting statistics on partitioned tables
Buffer cache: using clock-sweep algorithm to find free buffers
Fake table aliases in queries

We're launching a new series of articles covering the changes coming up in PostgreSQL 19. This first article focuses on the events from last summer's July CommitFest.

Connection service file in libpq parameter and psql variable
regdatabase: a type for database identifiers
pg_stat_statements: counters for generic and custom plans
pg_stat_statements: FETCH command normalization
pg_stat_statements: normalizing commands with parameter lists in IN clauses
EXPLAIN: Memoize node estimates
btree_gin: comparison operators for integer types
pg_upgrade: optimized migration of large objects
Optimized temporary table truncation
Planner: incremental sort in Append and MergeAppend nodes
Domain constraint validation no longer blocks DML operations
CHECKPOINT command parameters
COPY FROM: skipping initial rows
pg_dsm_registry_allocations: dynamic shared memory (DSM) usage

Hello everyone!

I want to note right away that this article is written exclusively for people who are just starting their journey in learning SQL and window functions. It may not cover complex applications of functions or use complicated definitions—everything is written in the simplest language possible for a basic understanding.

P.S. If the author didn't cover or write about something, it means they considered it non-essential for this article)))

For the examples, we will use a small table that shows student grades in different subjects. In the database, the table looks like this:

Some IT companies say they support open source. In practice, that often boils down to using other people’s code and a bit of PR. We believe real contribution means commits to the core. And to do that consistently, we opened an engineering center not in a glossy capital business park, but in a place where fundamental science is part of the cultural DNA. Here’s why we’re building the future of systems programming in Novosibirsk Akademgorodok.

Throughout their careers engineers build systems that protect data and guard it against corruption. But what if the right approach is the opposite: deliberately corrupting data, generating it out of thin air, and creating forgeries indistinguishable from the real thing?

Maksim Gramin, systems analyst at Postgres Professional, explains why creating fake data is a critical skill for testing, security, and development — and how to do it properly without turning your database into a junkyard of “John Smith” entries.

Technical support comes in many shapes. Sometimes it’s "try rebooting" or "check the cable." And sometimes it’s deep engineering work you wouldn’t mind dedicating your whole life to. Which version lives inside Postgres Professional, and what’s more important in this field — people or tech? We dig into this with Kamil Karimov, Senior technical support engineer at Postgres Professional.

In the big data era, data is one of the most valuable assets for enterprises. The ultimate goal of data analytics is to power swift, agile business decision making. As database technologies advance at a breathtaking pace in recent years, a large number of excellent database systems have emerged. Some of them are impressive in wide-table queries but do not work well in complex queries. Some support flexible multi-table queries but are held back by slow query speed.

Each type of data has a data model that best represents them. However, in real business scenarios, there is no such thing as ultra-fast data analytics under the perfect data model. Big data engineers sometimes have to make compromises on data models. Such compromises may cause long latency in complex queries or damage the real-time query performance because engineers must take the trouble to convert complex data models into flat tables.

New business requirements put forward new challenges for database systems. A good OLAP database system must be able to deliver excellent performance in both wide-table and multi-table scenarios. This system must also reduce the workload of big data engineers and enable customers to query data of any dimension in real time without worrying about data construction.

Apache Druid has been a staple for real-time analytics. However, with evolving and sophisticated analytics demands, it has faced challenges in satisfying modern data performance needs. Enter StarRocks, a high-performance, open-source analytical database, designed to adeptly meet the advanced analytics needs of contemporary enterprises by offering robust capabilities and performance.

In this article, we’ll explore the functionalities, strengths, and challenges of both Apache Druid and StarRocks. Using practical examples and benchmark results, we aim to guide you in identifying which database might best meet your data needs.

Migration from Oracle to vanilla PostgreSQL hits roadblocks with packages, autonomous transactions, and collections—they simply don’t exist there. We’ll break down why ora2pg stumbles, how native implementations of these mechanisms in Postgres Pro Enterprise make life easier, and how ora2pgpro translates PL/SQL semantically correctly, without hacks or crude regex.

September 25th marks the release of PostgreSQL 18. This article covers the March CommitFest and concludes the series covering the new features of the upcoming update. This article turned out quite large, as the last March CommitFest is traditionally the biggest and richest in new features.

You can find previous reviews of PostgreSQL 18 CommitFests here: 2024-07, 2024-09, 2024-11, 2025-01.

Filename Extension: .6nf

6NF File Format is a new bitemporal, sixth-normal-form (6NF)-inspired data exchange format designed for DWH and for reporting. It replaces complex hierarchical formats like XBRL, XML, JSON, and YAML

pg_stat_statements is the standard PostgreSQL extension used to track query statistics: number of executions, total and average execution time, number of returned rows, and other metrics. This information allows to analyze query behavior over time, identify problem areas, and make informed optimization decisions. However, in systems with high contention, pg_stat_statements itself can become a bottleneck and cause performance drops. In this article, we will analyze in which scenarios the extension becomes a source of problems, how sampling is structured, and in which cases its application can reduce overhead.