Maintenance of the logical consistency in Cassandra – Pablo SuA?rez-A�tero

Contrary to the relational databases, in NoSQL databases like Cassandra is veryA�common that duplicity of data in different tables happens. This is because usuallyA�tables are query driven (designed based on queries) and there are not anyA�relationships between them, in order to increase the performance of the queries.A�Therefore, if the data is not updated on a proper way, inconsistencies in the storedA�information could appear. It is quite easy to introduce defaults that causeA�inconsistencies of the data in Cassandra, especially during the evolution of aA�system where new tables are created, being these ones hard to detect usingA�conventional techniques of dynamic testing. The developer is the one responsibleA�for the maintenance of this consistency incorporating and updating the properA�procedures. In this session, a preventive approach to these problems isA�introduced, establishing the procedures required to ensure the quality of data fromA�the point of view of their consistency and thus helping the developer. TheseA�procedures include a static analysis using the conceptual model, the queries andA�the logical model of the application. They also include the determination andA�execution of the operations that guarantee the consistency of the information.