PGConf.Russia 2021

From the very beginning of 2021, I'm fixing a bug in CREATE INDEX CONCURRENTLY. This bug manifests extremely seldom. I could not find any traces of it in mailing lists ever since the introduction of the feature in 8.2. Yet the bug affected our systems, so I decided to fix it. This is how the9i detective bug-hunting story started. In this story, I'll share details of the implementation of transactions and lock mechanics.

When working with PostgreSQL, we regularly encounter queries that take suspiciously long to be executed. What if it's too late to enable statistics or auto explain, and cancellation of the query doesn't look sensible, but you still need to find out what caused the issue or see at what stage execution the query is? pg_query_state is an open source PostgreSQL extension, which can give you access to the query execution plan in real time. It also makes available statistics for each node, including the number of processed rows.

I will not teach you database design or query optimization. This talk will cover Python drivers, PostgreSQL usage in Python, and various tools from sync and async world enabling such usage, and how this ecosystem evolved. We'll discuss Python libraries including aiopg, psycopg2, asyncpg, pgbouncer and how they interact with Postgres.

Mamonsu is an active monitoring agent for PostgreSQL based on Zabbix. Mamonsu 3.0 Major Update includes new metrics and more possibilities for data visualization via Zabbix screens. It also introduces the improved functionality of Mamonsu tools for interacting with the DBMS. In addition to the new functionality overview, I will also share the nuances of upgrading to the 3.0 version.