Usage of Apache Cassandra for Prototyping the Event Metadata System of the NICA Experiments

Nuclotron-based Ion Collider fAcility (NICA) experiments at the Joint Institute for Nuclear Research have already generated substantial volumes of simulated and experimental (BM@N facility) data, and it is expected that the overall number of the collected events will increase from the current value of hundreds of millions to several billion events per year. An information system based on the event database (Event Catalogue) is required to store and index information on the events obtained at the NICA facilities, enabling quickly searching and using only necessary physics events based on various criteria for further processing and analysis. The paper describes the development of the Event Catalogue based on Apache Cassandra database. It is argued that Cassandra provides acceptable performance and is a possible candidate for creating the Event Catalogue in NICA and similar experiments. Principles of creating the database objects, in particular selecting the tables’ primary keys, are formulated.