PGConf.Russia 2025

The focus of the presentation is on the challenges of building an application solution on PostgreSQL, specifically a high-load analytical data warehouse. Using the case of the company EVRAZ, we will demonstrate the impact of applying the Data Vault methodology on PostgreSQL and Greenplum databases for developing a unified production performance system.

We will discuss the difficulties and solutions, showcasing query plans for tasks such as updating directories and handling large objects, along with optimization examples. We will highlight coding nuances, problems related to populating the model, and issues with querying from the model.

This session will be useful for those planning to use or already facing challenges with the Data Vault methodology and performance issues in DWH on the open-source stack. We will compare technical implementation options for the Business Vault model layer, considering the specifics of PostgreSQL and Greenplum.

We will also cover 5 real problems that arise when operating a DWH and their solutions:

1. Transferring Business Vault object assembly logic from PostgreSQL to Greenplum.
2. Slower ETL performance when building the current state of Business Vault in PostgreSQL.
3. Slower Data Lineage construction in PostgreSQL and Greenplum.
4. Slow satellite queries in Greenplum.
5. Slow queries with "IN" or "OR" in the Business Vault layer.

Dozens of PostgreSQL instances have replaced a single large Oracle database. One of our key business systems was completely redesigned and rebuilt on an import-independent solution.  

This talk will cover the unique challenges, architecture, issues, and operational aspects of this migration. Expect an insightful deep dive into the process!

Although we often don't like to talk about it, database administration carries with it a large amount of stress. This is particularly true when we have to take on late night support duties. In this talk you will learn: 1. The basics of the physiology of stress. This is not a physiology lecture, but as engineers we need enough to build a mental model. 2. What kinds of mistakes we make when under stress. 3. How to measure stress in your own life and recognize it in others. 4. What tools are helpful to manage short- and long-term stressors. Managing short-term stress is important in avoiding becoming overwhelmed when problems occur, but managing longer-term stressors is just as important in avoiding problems in the first place.

In this talk, we will discuss what character encodings and collations are. I will explain the issues that can arise from sorting (COLLATION) in databases and show how these problems can be addressed using the COLLATION PROVIDER = ICU feature in PostgreSQL.