PGConf.Russia 2022

Mamonsu is an active monitoring agent for PostgresSQL based on Zabbix. We are actively developing the agent: there are new unique metrics and visualization capabilities. But in addition to metrics collecting mechanism, Mamonsu has other useful features. I am going to briefly describe these features also known as "Mamonsu tools", the agent's advantages and the installation process.

In this presentation, we'll talk about the newest SQL/JSON features committed to PostgreSQL 15. We'll explain how to use them, where they can help and why they make a difference. Is PostgreSQL JSON implementation fully compliant with SQL:2016? In the meantime, the next generation of the SQL standard is being developed. What will the new standard include, and how will Postgres respond to it?

Previously, we have explained the internals of Avito, discussed, where and how we store your classifieds, and how they appear on the search results. In the recent 3-4 a lot has changed in Avito. We got rid of logical replication, stopped using standby servers for reads, removed nearly all stored procedures and our custom failover solution, migrated all our classifieds into a sharded DBMS, switched from the monolith app to microservices. I'll explain why we made such decisions, list some of the problems we encountered and describe the current state of our development process.

This presentation is about NULLs implementation in the Postgres database: - What is NULL? - How is it handled by various Postgres functions? - How are NULLs stored in the database? - Indexing of NULLs