PGConf.Russia 2022

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?

This talk covers the Oracle-to-Postgres Pro migration project for the billing system of the Federal State Unitary Enterprise “State Air Traffic Management Corporation of the Russian Federation” employed to collect the air navigation charges for the use of airspace.

PostgreSQL has a number of peculiarities that you need to take into account not only while maintaining your database but also when designing your database schema. Experienced PostgreSQL are well aware of vacuuming process. On the web one can find tons of materials covering its internals, configurations and monitoring. Many valuable talks about vacuum were given at numerous conferences. However, we still face the common wraparound problem when the maximum possible number of transactions (xid) is reached. It happens even on databases that are relatively small in size. In my presentation, I will share a customer case that looks interesting to me. A chain of mistakes made at different stages of the database's life cycle once caused a disaster. The database fully stopped for one week, we detected a wraparound and spotted corrupted blocks. Maintenance was problematical, and we spent sleepless nights in search of a solution. We managed to achieve a local win as we finally restored the database, but it's not the end of this story, which makes it even more interesting.

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