When working with a data warehouse application like SAP BW/4HANA or SAP Data Warehousing Foundation (DWF) it is usually not necessary to know what happens ‘under the hood’ – the interaction between the application, operating system, database and other services. The fact that the application architecture on the SAP HANA platform is undergoing a major change might seem irrelevant to data warehousing professionals. However, migration is mandatory and the recently-introduced features for data warehousing are only available in the new application architecture. In this blog post, Jan van Ansem explains what data warehouse designers and developers need to know about the changes.
Goodbye HANA XS (classic) and hello HANA XS Advanced
The HANA platform contains an integrated framework for application development, with an application server, web server and a programming environment for open standards. This framework is called ‘Extended Application Services’ (XS). There are currently two versions of XS running on the HANA platform: The old ‘XS classic model’ (XS) and the newer ‘XS Advanced model’ (XSA). The differences are explained by Thomas Jung, in his blog post “SAP HANA SPS 11: New Developer Features; XS Advanced”. For most data warehousing professionals, it is enough to know the following:
- XSA comes with a much-improved user interface
- Recently released features are only available in XSA
- Applications belonging to SAP’s Data Warehousing Foundation require XSA
- Some widely used XS functions will no longer be available in versions after HANA 2.0.
Improved user interface
A lot of SAP Data Warehouse development is done in HANA Studio. It might come as a shock to some to see that HANA Studio will be discontinued. Just now we finally had most tools in one place, things will change again. Of course, the recent introduction of the SAP BW/4HANA cockpit (a Fiori / web- based application) was a sign of changes to come. It is not yet clear when HANA Studio will be discontinued, nor what is going to happen with the BW tools, which are currently a plug-in for the Eclipse environment. With project Blueberry in mind (BW/4HANA as a cloud service) it seems a safe bet that the BW tools will be re-implemented in Fiori as a web-based application. (See BW/4HANA overview here, slide 19-23 for Project Blueberry).
Currently, HANA native development for Data Warehousing (tables, calculation views, SDI processes) can be done using the web IDE or in HANA Studio. As it happens, XS and XSA each have their own dedicated WebIDE. Below are screenshots of both:
The old, and for most people in SAP Data Warehousing familiar, WebIDE, (XS WebIDE, or to give it its proper name, the “SAP HANA Web-based Development Workbench”) The new XSA WebIDE The difference between old and new is immediately clear, with the eye catching big black border in the new look. You would be wrong to think the differences are purely cosmetic though. There are large differences in functionality. I will mention some of those differences in the next paragraph.
XSA – new features and a new way of working
In the XSA WebIDE you will not be able to find your familiar packages or old calculation views (created in XS). You have now stepped into the world of HANA Deployment Infrastructure (HDI) and should familiarise yourself with the concept of containers. Here is a tutorial to get you started. There are still Calculation Views in XSA but they look different and, more importantly, they have some cool new features. Let’s take a closer look at the palette of available node types when creating a calculation view in : The new node types for Calculation View design are:
- Non-equi join
- Graph node
- Table Function
- Hierarchy function
These are some interesting tools to have in the toolkit. Unfortunately, you must be on XSA first to use them!
New out-of-the-box applications build on XSA
SAP has introduced several new applications on the HANA platform to support Big Data Warehouse scenarios. I will just highlight two of these applications here, with some links to further information:
- Data Warehousing Foundation (provides functions like HANA Native DataStore Objects (NDSO’s), Data Warehouse Scheduler/Monitor and Data Lifecycle Manager. Read more in this blog).
- Enterprise Architect Designer (Tool for designing, analysing and sharing your strategies, requirements, processes, data and IT landscape. Here is an interesting blog. There is also an OpenSAP training course).
These tools are built to work with XSA objects and there is no or only limited support for XS objects. It seems that all the good stuff is happening in XSA and it is time to get on with it!
Except, there is a catch. The SAP Business Warehouse applications (BW on HANA, BW/4HANA) are not ready for XSA yet. If you create a Calculation View in XSA and use this cool new Anonymization function, then you’ll find that you cannot use this Calculation View in your BW Composite Provider. Bummer. SAP is working on making BW/4HANA work with XSA but at the time of writing no timeline was published for this change.
Depreciated XS functions – be aware
Whilst reading up on XSA, the main shock for me came when I realised that XS is going to be phased out. This means that the objects and functions we are now familiar with, will no longer work in future versions of SAP HANA. HANA Studio will disappear, as will the XS WebIDE. Database artefacts directly deployed in XS will no longer be supported, including Calculation Views. To put this in perspective, every single BW on HANA application and BW/4HANA application I have been working on have these objects.
The most widely used object is the Calculation View, but in many places HANA native tables and other object types are in use as well. The concept of the repository, including the object owner ‘_SYS_REPO’ will disappear as well. Take a look at SAP note 2465027 for more details but make sure you sit down before you do so because you might be in for a shock!
There are migration tools available for moving from XS to XSA (see this blog). When migrating, you must prepare yourself at least for significant conversion testing and you might need to re-design parts of your HANA native implementation.
The road ahead is yet unclear
SAP has not yet announced how much longer XS will be supported. Nor is it clear when BW will be compatible with XSA objects. This makes it difficult to plan. Another complicating factor is that it is hard to find the information about XSA which is relevant to data warehousing professionals. There is no lack of information about XSA in general (for example the SAP HANA Academy on YouTube offers a ‘SAP HANA XS Advanced Model’ channel with 111 videos). Most of this information is targeted at application developers, not at data warehousing.
It is still early days for XSA in the context of data warehousing. I trust the best practices and training material will materialise over time, to help the data warehouse community to get to grips with the new XSA architecture. One thing is sure though, the mandatory change from XS to XSA will not go unnoticed for data warehouse developers.