1.3 Implementing SAP BW/4HANA
SAP BW/4HANA can be implemented in one of the following three ways:
- New installation of SAP BW/4HANA
- System conversion of an existing SAP BW system
- Landscape consolidation of more than one SAP BW system into one SAP BW/4HANA
Figure 1.8 SAP BW/4HANA Transition Paths (Source: SAP)
The three transition paths are illustrated in Figure 1.8. We’ll discuss these options in the next subsections.
1.3.1 New Installation of SAP BW/4HANA
Installing a new SAP BW/4HANA system is currently the most common way to implement SAP BW/4HANA. This approach is referred to as greenfield because it involves a clean installation of SAP BW/4HANA, with no customizations, objects, or legacy programs that need conversion. The new installation option will be covered in detail in Chapter 3.
Some companies decide to install a new SAP BW/4HANA system even when they have a legacy SAP BW system for a fresh start and to move only the customizations that they want to retain to the SAP BW/4HANA system. This approach can be costly, as these companies end up with two systems running in parallel over a significant period, which results in increased support costs. In addition, we’ve seen that this approach also has significant development costs, as each development is evaluated and optimized for SAP BW/4HANA.
1.3.2 System Conversion of Existing SAP BW System
SAP BW/4HANA is a new product, as noted previously. This means that moving to SAP BW/4HANA doesn’t just upgrade an existing SAP BW system. The move to SAP BW/4HANA from an existing SAP BW system therefore requires a few steps.
The first step is to migrate the system to SAP BW powered by SAP HANA 7.5 and then convert all objects to SAP HANA-supported objects, such as Advanced DSOs and CompositeProviders. SAP provides an interim release called SAP BW powered by SAP HANA with SAP BW/4HANA starter add-on or SAP BW, edition for SAP HANA, which allows for prechecks and conversions to take the place of legacy objects using SAP-delivered tools.
One transfer tool that allows for a complete dataflow transfer can be executed with Transaction RSB4HTRF (see Figure 1.9).
Figure 1.9 Transaction RSB4HTRF: Dataflow Transfer Tool to SAP BW/4HANA
This tool will create a new dataflow with SAP BW/4HANA-compatible objects but will not transfer the data. The tool currently supports conversion of the object types listed in Table 1.3.
| Old Object Type | New Object Type |
|---|---|
| DSO | Advanced DSO |
| InfoCube | Advanced DSO |
| MultiProvider | SAP HANA CompositeProvider |
| CompositeProvider (object type COPR) | CompositeProvider (see also SAP Note 2080851) |
| HybridProvider (InfoCube plus DSO) | Advanced DSO |
Table 1.3 Object Conversions Supported in Transaction RSB4HTRF
Process chains and other objects aren’t converted or copied.
Note
See more details in SAP Note 2238220 (BW on HANA: Transfer Enhancements).
Another tool available is program RSO_CONVERT_IPRO_TO_HCPR, which converts SAP BW InfoProviders to CompositeProviders. This tool allows for conversion of an existing InfoProvider, including its queries, into an SAP HANA CompositeProvider, with options to simulate and create a backup of the old InfoProvider and move or copy the queries (see Figure 1.10).
Figure 1.10 RSO_CONVERT_IPRO_TO_HCPR Program Selection Screen
A conversion tool for Advanced DSOs, including data conversion, is still in development, but the conversion tools are evolving quickly. SAP’s development roadmap for SAP BW/4HANA predicts the tools being completely delivered in 2017.
However, the process of converting an existing SAP BW system to SAP BW/4HANA currently has quite a few limitations, as add-on components like SAP BPC “classic” is not supported.
Note
SAP Note 2383530 (Conversion to BW/4HANA—Step-by-Step Description) contains the detailed steps required to perform a conversion from SAP BW 7.5 to SAP BW/4HANA.
1.3.3 Landscape Consolidation
Companies with multiple SAP BW systems sometimes target consolidating their systems into one SAP BW/4HANA system going forward. This process requires a lot of analysis of configuration differences and data harmonization. SAP is innovating some tools to help, such as the System Comparison Workbench, which can be used to find differences between, for example, regional SAP BW systems.
The landscape consolidation approach isn’t specific to SAP BW/4HANA; it has been applied over the past 18 years in other SAP BW system consolidations. Most issues that arise generally center on master data harmonization, which requires setting up a master data management process and maybe an MDM system to ensure that master data stays clean and harmonized across regions.
The landscape consolidation, or transformation, as it’s sometimes called, can be performed by consolidating into a new SAP BW/4HANA system or into one existing SAP BW system, which is then converted to SAP BW/4HANA. Which option to choose normally depends on the type of system and how much content should be retained.
1.3.4 Recommendation for Implementing SAP BW/4HANA
The implementation of SAP BW/4HANA can be difficult when there is significant investment in the SAP BW system. It’s generally recommended to go the route of system conversion, especially when a majority of the content in the legacy SAP BW system is still required in the SAP BW/4HANA system. The benefits that companies have gleaned with just the technical migration of their legacy SAP BW systems to SAP BW powered by SAP HANA can provide fast and real success as part of the longer road of moving to SAP BW/4HANA. Table 1.4 shows guidelines for choosing a path. The clear option if you have an SAP BW system powered by SAP HANA is to move forward with conversion to SAP BW/4HANA. A new installation and rebuild of the SAP BW/4HANA system is possible for all scenarios, but should be considered against the cost and effort of having two systems running for a significant amount of time.
| Starting Point | Path 1: New Install | Path 2: System Conversion | Path 3: Landscape Transformation |
|---|---|---|---|
| One or more legacy systems | Possible alternative path | Not supported | Possible alternative path |
| SAP BW on any DB | Possible alternative path | Possible alternative path | Possible alternative path |
| SAP BW powered by SAP HANA | Possible alternative path | Recommended path | Possible alternative path |
| SAP BW, edition for SAP HANA | Possible alternative path | Highly recommended path | Possible alternative path |
| Multiple SAP BW systems | Possible alternative path | Not supported | Highly recommended path |
Table 1.4 Paths to SAP BW/4HANA