NOSOLAP: Moving from Data Warehouse Requirements to NoSQL Databases

Typical data warehouse systems are implemented either on a relational database or on a multi-dimensional database. While the former supports ROLAP operations the latter supports MOLAP. We explore a third alternative, that is, to implement a data warehouse on a NoSQL database. For this, we propose rules that help us move from information obtained from data warehouse requirements engineering stage to the logical model of NoSQL databases, giving rise to NOSOLAP (NOSql OLAP). We show the advantages of NOSOLAP over ROLAP and MOLAP. We illustrate our NOSOLAP approach by converting to the logical model of Cassandra and give an example.