PgConf.Russia 2020

MobilityDB is an open source moving object database system (https://github.com/ULB-CoDE-WIT/MobilityDB). Its core function is to efficiently store and query mobility tracks, such as vehicle GPS trajectories. It implements the Moving Features specification from the Open Geospatial Consortium (OGC). MobiltyDB is engineered up from PostgreSQL and PostGIS, providing spatiotemporal data management via SQL. It thus integrates with the postgreSQL eco-system allowing for complex architectures such as mobility stream processing and cloud deployments.

The presentation will explain the architecture of MobilityDB, its database types, indexes, and operations. We will highlight the PostgreSQL features that enable this extension, and the would like to have features. This presentation will be of special interest to the PostgreSQL community, and to professionals in the transportation domain.

Everyone has heard something about transaction isolation levels, but oddly enough, almost no one can clearly explain what it is any why it is important. At the same time, for many operations, it is critical to have a clear understanding of isolation levels and how they can affect the result. Indeed, if a customer has been paid twice and the developer has to pay back the losses, it won't seem unimportant. We'll discuss how to avoid such unpleasant situations.

pg_repack is one of the most popular instruments for removing bloat of tables and indexes in Postgres. In most cases, it works perfectly. But if you use such a feature of Postgres as deferred constraints, using pg_repack becomes more difficult or even impossible. I will talk about how we encountered the problem and will describe some workarounds - from internal instruments of Postgres to a small patch for pg_repack.

We will discuss stored procedures and functions, as well as the code within the database in general. We'll take a look at stored procedures from different angles: as a DBA, a database developer, and a backend developer. We will try to understand the specifics of stored procedures that often go against the common coding guidelines, and discuss best practices for working with stored procedures.
This is mainly a motivational talk for database and backend developers, not an advanced tech talk.