From conceptual to logical ETL design using BPMN and relational algebra

"Extraction, transformation, and loading (ETL) processes are used to extract data from internal and external sources of an organization, transform these data, and load them into a data warehouse. The Business Process Modeling Notation (BPMN) has been proposed for expressing ETL processes at a conceptual level. This paper extends relational algebra (RA) with update operations for specifying ETL processes at a logical level. In this approach, data tasks can be automatically translated into SQL queries to be executed over a DBMS. An extension of RA is presented, as well as a translation mechanism from BPMN to the RA specification. Throughout the paper, the TPC-DI benchmark is used for comparing both approaches. Experiments show the efficiency of the resulting ETL flow with respect to the Pentaho Data Integration tool."