PGConf.Russia 2025

t’s well known that pg_upgrade is the go-to tool for fast PostgreSQL upgrades. However, even with this tool, there are cases where the upgrade process takes far longer than expected.

In our case, upgrading a PostgreSQL database with 350,000 tables meant either waiting 3.5 hours or finding a better approach. By digging into the pg_upgrade source code, we discovered a way to speed up the process significantly. In this talk, we’ll share how we did it.

Greenmask is an open-source utility for database anonymization and synthetic data generation. A common challenge in development is creating test environments that closely resemble production. In this talk, we will explore how to use Greenmask’s features to prepare a test environment with ease. 

We will discuss its architecture, database subsets, types of transformations, the reasons for integrating with the PostgreSQL driver, and porting some pg libraries. Additionally, we will explain how our technology helps businesses solve problems faster, more efficiently, and securely.

Experience Report addressing the manual migration of MS SQL Server Stored Procedures and Table-Valued Functions to PL/pgSQL. We chose a manual migration from T-SQL over using a PostgreSQL Extension with an automated translation. The motivation was that the T-SQL code contains non-trivial business logic for which we wanted idiomatic PL/pgSQL code. 

The T-SQL Code used features like 

• Mix of Stored Procedures and Table-valued Functions

• Table variables, (user-defined) table types 

• Recursive Common Table Expressions 

• Optional parameters 

The migration required

• Adopting naming conventions 

• Renaming parameters and local variables 

• Maping table types 

• Mapping table-valued parameters to arrays 

• Mapping table-valued return types to SETOF record

• Translating between arrays and tables 

In this session we will migrate a chain of dependend functions T-SQL functions to PL/pgSQL. We will work around quirks in both T-SQL functions and PL/pgSQL.

The work of a DBA is very multifaceted: backups, version updates, performance issues — there's a long list. But sometimes, due to the workload, we don't give enough attention to innovations that don't directly relate to what we do every day. Such is the case with logical replication.

Of course, each of us has some skills working with this tool, but PostgreSQL is a rapidly evolving database system. Sometimes, we simply need to look around with a fresh perspective to see something new.

My presentation will be based on this approach: we'll start with theory (as always, less theory, more practice) and simple examples, then move on to more complex examples of its use. Special attention will be given to what has changed in modern versions of PostgreSQL.

This presentation will be helpful for those who want to get acquainted with logical replication or refresh their knowledge of this tool.