Modelling ETL processes of data warehouses with UML activity diagrams

Abstract

Extraction-transformation-loading (ETL) processes play an important role in a data warehouse (DW) architecture because they are responsible of integrating data from heterogeneous data sources into the DW repository. Importantly, most of the budget of a DW project is spent on designing these processes since they are not taken into account in the early phases of the project but once the repository is deployed. In order to overcome this situation, we propose using the unified modelling language (UML) to conceptually model the sequence of activities involved in ETL processes from the beginning of the project by using activity diagrams (ADs). Our approach provides designers with easy-to-use modelling elements to capture the dynamic aspects of ETL processes.