PGConf.SPB 2023

Fuzzing research is feeding random input data to a program (or a part of it) (in fact, randomness is very conditional) and seeing what we get out of it. And we repeat it many times on many processors.

Fuzzing a large monolithic program complex is never a simple task. It requires extraordinary solutions. In this talk, I will tell you what and how we searched with the help of fuzzing and what results it led to.

• Investigation of data type parsing functions (input-functions): for warming up;
• Investigation of functions implementing operations between types (op-functions): it is better to consider the structure here;
• Network subsystem fuzzing: let's pretend we are POSIX calls, it's cheaper that way;
• Recovering disk context: we need Groundhog Day.

A story about funny bugs and ridiculous hand gestures will be included.

Facing the restrictions on the use of Western software, our bank has developed and put into commercial operation a reliable mechanism for data replication between two DBMSs. This mechanism allowed the bank's teams without any special restrictions to replace the product from Oracle (Oracle Golden Gate was previously used in the bank for a long time). In the presentation, we will talk about the main advantages of our software and the nuances of its use.

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.

Postgres Pro is investing heavily to make it easy for customers to migrate to their database from Oracle Database.

This talk describes in detail the advanced Postgres Pro DBMS technologies designed to solve this problem:

• support for package functionality in PL/pgSQL, including the package initialization section and global package variables;
• ora2pgrpo utility for automatic conversion of package code from Oracle PL/SQL syntax to PL/pgSQL;
• PG Pro Application Info extension designed for instrumentation and monitoring of the state of sessions, including the execution of long operations (session longops) - a functional analogue of the package DBMS_APPLICATION_INFO in Oracle DBMS;
• new system packages UTL_MAIL and UTL_SMTP for sending emails from stored procedures to Postgres Pro DBMS (full functional analogue of the corresponding packages in Oracle DBMS);
• new system package UTL_HTTP for interacting with external sources from stored procedures in Postgres Pro DBMS (analogous to the package of the same name in Oracle DBMS);

Also in this talk there will be a short story about the directions of development of the Postgres Pro DBMS aimed at further simplifying migration from Oracle DBMS.