5    Data Modeling

In this chapter, we discuss the modeling objects available in SAP BW/4HANA and how these elements can be configured to address typical data warehousing requirements, ranging from data virtualization to persistency, as well as agile reporting functionality.

To summarize data modeling with SAP BW/4HANA in three words: Less is more. Less because a reduced number of modeling objects is offered in SAP BW/4HANA compared to the SAP NetWeaver-based SAP BW application. More because these modeling objects, though reduced in number, are more versatile, pack together more features, and offer greater modeling flexibility than the several SAP BW applications combined.

In this chapter, we’ll describe the SAP BW/4HANA modeling objects in detail, covering their features, their purposes, and how they can be configured using the BW modeling perspective of SAP HANA Studio. We’ll discuss elements from the smallest SAP BW/4HANA modeling entities—known as InfoObjects and considered the information building blocks—to sophisticated information models represented by Advanced DSO and CompositeProviders—the former primarily acting as a persistent layer of SAP BW/4HANA and the latter having the role of a logical layer. The open integration nature of SAP BW/4HANA is reinforced by the availability of the Open ODS view modeling object, which corresponds to an agile data virtualization layer.

5.1    Modeling Perspectives

SAP BW modelers are very familiar with Transaction RSA1, which has been central to SAP BW since its inception. This transaction accesses the SAP BW Administrator Workbench, the main UI for performing tasks in data warehousing such as data modeling functions, as well as data loading control, monitoring, transport management, and maintenance processes.

Figure 5.1 shows the well-known Administrator Workbench, Transaction RSA1, in SAP BW. The left-side panel of the UI shows the many functionality groups available, with the Modeling functionality highlighted.

SAP BW Administrator Workbench

Figure 5.1    SAP BW Administrator Workbench

When accessing the same Administrator Workbench using Transaction RSA1 from SAP BW/4HANA, however, there’s a striking difference. The modeling option of the left-side panel is absent, as shown in Figure 5.2.

SAP BW/4HANA Administrator Workbench

Figure 5.2    SAP BW/4HANA Administrator Workbench

The reason for this change is that modeling activities in SAP BW/4HANA are performed solely within Eclipse-based SAP HANA Studio. That doesn’t mean that Transaction RSA1 has been made entirely obsolete; activities such as data load control, monitoring, authorization definition, and data source maintenance are still performed via the classic SAP BW Administrator Workbench.

Note

As SAP continues to migrate features from SAP NetWeaver to SAP HANA Studio, the SAP BW Administrator Workbench will eventually be made obsolete for SAP BW/4HANA.

The central SAP BW/4HANA modeling UI is the BW modeling perspective available in SAP HANA Studio. To access this perspective, choosing the SAP HANA studio • Window • Perspective • Open Perspective • Other… menu path and select BW Modeling from the list of available perspectives.

The first step for data modeling in SAP BW/4HANA is to set up a BW project if one isn’t yet available. A BW project acts as a system connection to a corresponding application server. It’s via a BW project that the metadata is exposed to SAP HANA Studio so that modeling activities can be performed.

Follow the menu path File • New • BW Project to create a new connection within the BW modeling perspective. The project type should be Business Warehouse, and the connection parameters should be entered as in the SAP Logon Pad; provide the SAP BW/4HANA system ID, client, user, and password.

Once you’ve defined a BW project, the next step is to connect to the SAP BW application layer by double-clicking the BW project itself. SAP HANA Studio will then connect to the corresponding application server and expose the repository of modeling objects, as seen in Figure 5.3, and organized under InfoAreas. InfoAreas are akin to folders into which modeling objects are organized.

Modeling Perspective Exposing Metadata RepositoryMetadata repository

Figure 5.3    Modeling Perspective Exposing Metadata Repository

Right-click an InfoArea of the BW repository to open a context menu. Select New… from the context menu to create the following elements:

The elements of interest for data modeling in SAP BW/4HANA are InfoObjects, Open ODS views, Advanced DSOs, and CompositeProviders. The following sections dive into each of these objects in detail, describing their modeling purposes and configuration steps.