Extraction, Transformation, and Loading - Data Warehouse Systems: Design and Implementation - page 286

Fig. 8.8 Swimlanes: pool and lanes
Fig. 8.9 BPMN artifacts: annotations
a gateway condition or the attributes involved in a lookup task, as shown in
Fig. 8.9 . Annotations may be associated with both activities and subprocesses
in order to describe their semantics.
8.2 Conceptual ETL Design Using BPMN
There is no standard conceptual model for defining ETL processes. Each
existing tool provides its own model, often too detailed since it takes into
consideration many particular implementation issues. In this section, we show
how BPMN can be customized for designing ETL processes at a conceptual
level. We describe how the BPMN constructs introduced in the previous
sections can be used to define the most common ETL tasks. We also introduce
a BPMN-based notation for ETL. The most obvious advantage of using a
conceptual approach for designing ETL processes is the ability to replicate
the same process with different tools. We will illustrate this fact by describing
in Sect. 8.3 the conceptual model of the ETL process that loads the Northwind
data warehouse. Then, in Sects. 8.5 and 8.6 , we will show how this conceptual
model can be implemented, respectively, in Integration Services and Kettle.