PGConf.Russia 2025

Two years ago, I spoke about data retrieval queries, where the LINQ to DB library offers almost limitless possibilities.

This talk is about data modification operations. LINQ to DB allows you to execute UPDATE + JOIN queries, INSERT FROM SELECT, supports the MERGE operator, row-level locking with SELECT FOR UPDATE, temporary table creation, and features a fast data insertion mechanism.

I will also discuss the linq2db. EntityFrameworkCore project — a solution for those who aren’t ready to leave EF Core but still want the capabilities of LINQ to DB. I’ll share our experience implementing LINQ to DB in a large-scale project.

Many Russian companies are striving to establish themselves in the relational database market by developing their own commercial solutions, often based on forks of vanilla PostgreSQL. But beyond the database itself, customers also need a graphical management tool — Enterprise Manager. Since forking it is extremely challenging, vendors often have to build their own from scratch while considering competitive solutions.

This talk will explore Enterprise Managers from various Russian database vendors, comparing their key features — functionality, usability, and design — to identify which one stands out as the most effective.

Making changes to tables under production load is always a complex task. For example, when you need to change a column type (e.g., from int to bigint or from timestamp to timestamptz), or move a table to a different tablespace without losing any changes that occur during the data migration.

What if you have hundreds of such tables? With pg-transparent-alter-table, this is no longer a problem. These tasks can be solved with a single simple command:
$ pg_tat -h 0.0.0.0 -d mydb -c "alter table mytable alter column id bigint"

Key features include:

• You can specify any number of alter table commands at once.
• You can modify partitioned tables, supporting both the old inheritance-based partitioning and new declarative partitioning, including multi-level partitioning.
• You can interrupt the process at any stage and continue later without losing progress from previous stages.
• You can change your mind at any time, stop the execution, run "pg_tat --clean," and revert to the original state.
• Custom commands for changing column order.
• PostgreSQL version support: 11-17.

After more than 5 years of existence (previously called transparent-alter-type), the project has become a reliable tool actively used in production. I would like to share my experience and discuss its capabilities.

Covering all the key changes in PostgreSQL 18 during this talk would be quite a challenge — especially since the code freeze is set to happen just a week after the presentation. However, I’ll focus on what has already been finalized.

There are plenty of exciting updates in performance, monitoring, vacuuming (of course!), and beyond. As always, this talk is based on a series of articles reviewing the commit fests for PostgreSQL 18, published on Postgres Professional’s corporate blog on Habr.