PGConf.SPB 2023

During the years of its existence, Postgres Pro piled up a pool of problems when query execution was inappropriately slow or a query was too expensive to be executed, so it was never executed. Almost always in our practice, this was due to the choice of a non-optimal query plan. In our story, we will talk about a very unconventional attempt to solve this problem by re-planning queries. We will tell you what it is, how it works, who will find it helpful and the prospects for using this feature.

We'll talk about the tool we created, which monitors changes in the database and creates scripts for migrations of selected objects both interactively and automatically.

One of the requirements for the operation of the Corosync/Pacemaker failover cluster is the fencing of the failed node. In virtual environments, fencing is implemented by disabling the virtual machine through a hypervisor, in a cluster on physical servers - through IPMI/ILO. But what if it is impossible to organize fencing, for example, in the cloud environment? During this presentation, I will list and explain alternative methods of fencing a failed node.

A talk on how regular™ indexes work in PostgreSQL. The talk will be extremely useful for those who are starting to work with databases, and for those who have worked with them but have forgotten. If the talk hits the golden picks of "must-see onboarding developer", then the goal is achieved.
We will tackle the following subtopics:
- How an index can speed up search;
- Should we index WHERE conditions;
- Should we index ORDER BY statements;
- Should we index foreign keys;
- What to do if search pre-assumes multiple conditions;
- Which column order should be specified in an index;
- Cases when index causes a slow-down and how to reduce its impact on the app.