The Road to SAP BW/4HANA - Part 2

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(Updated January 2019)

In the first part, we looked at the different paths to get to SAP BW/4HANA. Now let's see which path makes the most sense for a given starting point of a customer's landscape.

One or More Legacy Systems

Unless you are a brand-new enterprise, your landscape will most certainly contain some databases or systems that are collecting various kinds of data. Now you realize that you need a way to define common semantics, harmonize data values, establish a ‘single version of truth’, and provide a single, comprehensive source of current and historical information across all these sources. You need a data warehouse... SAP BW/4HANA. The obvious path is to install a new SAP BW/4HANA system, connect all your data sources, and either load the data (traditional ETL) or consume the data remotely (logical data warehousing). Of course, you want to put some thought into modeling and structuring your SAP BW/4HANA data warehouse, so we recommend defining a layered scalable architecture that suites your requirements best based on the LSA reference framework provided by SAP.

Instead of rebuilding your legacy system or data warehouse completely in SAP BW/4HANA, you could move some or all of it directly into the SAP HANA database that SAP BW/4HANA is running on (in a separate database schema or tenant). You can then leverage the content using mixed models between SAP BW/4HANA and SAP HANA views.

If you have a complex landscape, want to replace legacy data warehouse(s), or simply need help on your way to SAP BW/4HANA, please consider the path of using services offered by the SAP’s Digital Business Services group. We will setup a project that will lead you to a successful implementation of SAP BW/4HANA.

SAP BW 7.5 powered by SAP HANA with SAP BW/4HANA Starter Add-on

If you are running this release of SAP BW, are exclusively using objects compatible with SAP BW/4HANA (Advanced DataStore Objects, Open ODS Views, CompositeProviders, etc.) as well as using SAP BusinessObjects or SAP Analytic Cloud as a front-end (or a supported third-party tool), then your system is mighty close to being ready for transitioning to SAP BW/4HANA. In-place Conversion is the way to go. Perform a system pre-check using the SAP BW/4HANA Transfer Cockpit. If you get all green lights, your system can be converted to SAP BW/4HANA! A few hours of downtime over the weekend will do the trick.

If you get some yellow lights during the check, then there are some objects left in your SAP BW system that need to be transferred to compatible objects using one of our tools. Should you get some red lights, you will have some to-dos: The object won’t work with SAP BW/4HANA and so far, there’s no tool support. The check will point to the corresponding Simplification Item and SAP Note, which documents options and next steps.

Although new installation or landscape transformation are possible paths, it's quite unlikely that you would go this way because the system is just one step away from SAP BW/4HANA.

SAP BW powered by SAP HANA

About 4,000 customers are running this release. Go, BW on HANA! If you started your SAP BW implementation recently or have kept your system up-to-date with release upgrades to 7.5, then you are in a comparable situation as customers who already use the SAP BW/4HANA Starter Add-on. If not, the In-place Conversion path still makes a lot of sense. Upgrade slightly older systems to release 7.5 and install the "SAP BW/4HANA Starter Add-on". If necessary, transfer classical to HANA-optimized data models and data flows. This might be the case, especially if you did technical upgrades and a straight migration from another database in the past and continue to use InfoCubes and classic DSOs i.e. you haven't fully transitioned to Advanced DSOs, CompositeProvider and Open ODS Views. The SAP BW/4HANA Transfer Cockpit and its Scope Transfer Tool will do this job for you.

If your system is still on release 7.3 and you are upgrading to 7.5, then you might have to adjust some of your custom code due to the change that came with 7.4. Please review SAP Note 1823174.

Generally, we recommend the system conversion path but in some cases, you might want to consider a new installation approach. SAP BW powered by SAP HANA systems can be over five years old (yes, SAP HANA has been around that long). If you don't want to go through the steps described above, you could go for a new SAP BW/4HANA instance, and perform a Shell Conversion. With this approach you transport objects and configuration. Data models and flows will be converted to SAP HANA-optimized versions at import into SAP BW/4HANA. You can then at your convenience load data from your source systems or the original SAP BW (until you decommission it). This will give you a clean start into the SAP BW/4HANA world.

Going one step further, a Remote Conversion will also transfer existing master and transaction data to your new SAP BW/4HANA system and keep it in sync with the original SAP BW.

SAP BW on Any Database (other than SAP HANA)

The most challenging scenario can be a SAP BW system still running on other databases than SAP HANA. To convert the complete system to SAP BW/4HANA will require a database migration, release upgrade, transfer to HANA-optimized objects, and custom code adjustments. A Unicode conversion will be required as well for non-Unicode systems. Still the In-place Conversion path is an option especially if you are very happy with what you have on SAP BW today. We have done migrations to SAP HANA many times now, so overall the process is well understood and can be executed smoothly. It comes down to the SAP HANA-optimization which is what the SAP BW/4HANA Transfer Cockpit will help with.

However, if your system is on release 7.3 or higher, the better choice is to go for a Remote Conversion. It lets you “jump” from SAP BW systems that haven’t been upgraded for years or run on clunky disk-based database platforms to SAP BW/4HANA and the in-memory SAP HANA database! You choose which data models and flows you like to convert and our tools will transfer them to a new SAP BW/4HANA system, including all required master and transaction data. And the best: We SAP HANA-optimize the models automatically.

For systems on the old 7.0x release, the Shell Conversion is the only option. Such old systems often need a rebuild, for example, to properly implement a layered scalelable architecture (LSA++). The Shell Conversion will help to take over the essential data models.

Multiple SAP BW Systems

We certainly see a trend to simplify landscapes and consolidate several SAP BW systems into a global instance running on SAP HANA. If you have multiple production SAP BW systems - typically split by region or line of business -, then we recommend checking out the Landscape Transformation path. It's best suited for customers, who want to consolidate their landscape or carve out selected data models and data flows into an existing SAP BW/4HANA system. SAP Digital Business Services offers packages in order to setup a customer-specific migration and conversion project. This will include re-using standard tools for example to compare the configuration and security of your SAP BW systems.

Alternative is to treat the situation the same way as described in the "One or More Legacy Systems" chapter.

SAP BW/4HANA - Which Path is Right for You?

Summary

We understand our customers are starting their journey to a modern data warehouse from various places. That’s why we have created three distinct paths, complete with distinct services and tools, to help you achieve your goals in the most direct fashion, with the least disruption.

For a presentation style version of this blog ("The Road to SAP BW/4HANA") and many more details on SAP BW/4HANA, please visit the SAP Community Network and check out the FAQ document.

A complete end-to-end documentation of the transition process from SAP BW to SAP BW/4HANA is already available in the SAP BW/4HANA Conversion Guide.

Continue reading "The Road to SAP BW/4HANA - Part 3".

Best,
Marc Bernard
@marcfbe