PgConf.Russia 2020

Postgres has always had strong support for relational storage. However, there are many cases where relational storage is either inefficient or overly restrictive. This talk shows the many ways that Postgres has expanded to support non-relational storage, specifically the ability to store and index multiple values, even unrelated ones, in a single database field. Such storage allows for greater efficiency and access simplicity, and can also avoid the negatives of entity-attribute-value (eav) storage. The talk will cover many examples of multiple-value-per-field storage, including arrays, range types, geometry, full text search, xml, json, and records.

Role-based access control (RBAC) is one of the main mechanisms used for access control in many DBMS, including PostgreSQL. This model is a sub-type of traditional discretionary access control with its restrictions. In addition to DAC, many operating systems also use mandatory access control (MAC) based on security labels. This additional security mechanism is obligatory for protecting information that demands higher levels of security. Naturally, we would like to use MAC within DBMS when working in OS with mandatory access control switched on.
In this talk, we'll give an overview of existing MAC implementations in DBMS, as well as share our approach to using security mechanisms provided by SELinux, the sepgsql extension for PostgreSQL, and the standard mechanism of row-level security (RLS), which has been available in PostgreSQL starting from version 9.5.
In our presentation, we will use the "Airlines" demo database provided by the Postgres Professional company to show how to protect sensitive information and personal data, compare different ways of storing security labels, and assess performance of our solution.

Moscow public transport vehicles when moving report their coordinates via GLONASS. Collected data is used for various analyses including timetable development, bottlenecks detection and planning the bus lanes. Until recently we used the PostGIS extension for this purpose but now we are switching to a new PG extension — MobilityDB — designed especially for geodata time series processing. I have compared the table size and the performance of our solution without and with MobilityDB and happy to present the results.

PostgreSQL is one of the most readily extensible databases in the world. Custom data types, aggregations, functions, and more can be easily and safely written in C.

This hands-on tutorial covers the basics of writing functions, data types, and aggregates in C. It is recommended (though not strictly required) that bring their own laptops and be prepared to actually try the exercises.

Topics covered include: 1. The PostgreSQL type system 2. Creating a simple custom type in C 3. Common errors for non-C programmers 4. Creating a simple aggregate in C

There will be many opportunities for questions and discussion through the tutorial.