PGConf.SPB 2023

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.

Recently, one of the most common migration methods has become migration using the free ora2pg tool. However, many note the extremely low performance of this tool, especially when it comes to databases of 1 Terabyte and above. This presentation describes how to significantly speed up database migration using oracle_fdw alone or in combination with ora2pg.

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.

Unfortunately, ideal computer systems exist only in science fiction books. PostgreSQL is not exception and sometimes problems may occur. I would like to discuss how to correctly (and incorrectly) try to solve a problem, which way to choose, which tool to use.

The talk is of interest to both beginners and experienced users and database administrators.