Does SAP HANA eliminate the need for an Enterprise Data Warehouse (EDW)?
Not at all. Although the SAP HANA database has the potential to eliminate the need in most cases for an Operational Data Mart, as the vision of Suite on HANA is to "re-import" all operational reporting back into the Business Suite, or as Hasso Plattner said, "putting the R for real-time back into R/3", there will still be a need for a data warehouse.
High level tasks of a data warehouse are generally accepted as:
• Integrating data from various data sources to common semantics given by the Data Warehouse data model
• Harmonizing data values
• Establishing a ‘single version of truth’ as a source for data marts, delivering a common view of enterprise data
• Providing a single, comprehensive source of current and historical information
A detailed look at this question was the focus of the SAPPHIRE/ASUG 2014 session 'Data Warehousing in the Age of In-Memory Computing and Real-Time Analytics'. You can find a copy attached at the bottom of this page.
Another interesting aspect regarding this topic is covered by the following blog.
Do we still need SAP BW or would we be only using the SAP HANA data models going forward?
You absolutely still need BW. The HANA DB is an excellent foundation and database for a BW Data Warehouse. In addition, HANA data models complement BW on HANA with agile data modeling for real-real-time data and non-SAP data. These HANA custom data mart data/schema can also be consumed in SAP BW. On the other hand, the SAP BW Business Content jumpstarts the deployment of a SAP HANA data mart.
Best of all, both BW and HANA data models reside on a single system (BW on HANA), minimizing admin overhead, capital investment and data redundancy, and the BW on HANA system can connect to a Sybase IQ NLS Near-Line-Storage solution.
SAP Executive Board Member and CTO Dr. Vishal Sikka made a very clear statement about the future of BW at TechEd 2013. Watch the following short interview.
http://events.sap.com/teched/en/session/8846# (the BW part starts around minute 8)
Thomas Zurek, VP Development – SAP HANA EDW + Business Warehouse, wrote an interesting blog about the different approaches of building a data warehouse in HANA, with BW and without.
What is the SAP 's view on BW?
SAP provides customers with multiple choices, and SAP BW is one of these choices. Modeling of a data warehouse requires a sophisticated toolset for security, governance, request handling, metadata management, out of the box functionality, pre-delivered content etc etc.
This is what BW is made for and will be our data warehouse solution going forward with an even stronger positioning. So-called operational data marts and agile data marts typically do not require a lot of integration and harmonization work with other data marts since they are build for a very specific purpose and audience. They are based on the entity relationship model, meta data and master data of the source system. Data Warehouses are made for integrating and harmonizing different sources and bring the data into one standardized model which is the basis for enabling global reporting. This requires a sophisticated solution.
BW is the perfect solution for this. Just think about the OLAP engine with all it's features! In the past we had to implement quite some operational reporting in BW due to lack of technology on the ERP side. This changed now with HANA where you can build those type of data marts directly with the HANA Modeler. And the best part is that BW runs on the same appliance, which means you have all types of data marts on the same appliance. Combining those data marts for consolidated reporting purposes is easy, e.g. with a BW TransientProvider that can consume any HANA model directly without any data replication.
BW has a bright future and is one of SAP's most strategic solutions. SAP Executive Board Member and CTO Dr. Vishal Sikka made a very clear statement about the future of BW at TechEd 2013. Watch the following short interview. The BW part starts around minute 8.
Is there a recommendation or best practice from SAP whether to build analytics natively and directly in HANA versus BW?
There is white paper that has been released by SAP that describes this in detail and discusses the difference in building analytics directly on top of HANA with HANA native data models versus building more data warehouse type of analytics based on BW (on HANA) data models.
Is there a best practice and guidance on how to consolidate several BW systems into one?
The migration to BW on HANA is a very good opportunity to reduce the complexity of a BW landscape by consolidating several BW systems into one. Read this blog to get more detailed information on how to do this.
Is there a good customer example and story on how to use BW as EDW?
Read this great and detailed blog from Martin Grob where he explains how his company implemented a successful BI strategy by leveraging BW as their EDW.
What size of an EDW can a BW system manage?
See this showcase at TechEd 2013 where a ½ Petabyte and 2.5 PB of data is managed by one single BW system.
What do analysts say about BW on HANA as an SAP EDW solution?
See this blog that links to some of the analyst reports including Forrester and Gartner.
Do Big Data solutions make data warehouses obsolete?
There is a lot of misconception around Big Data and Data Warehousing. Please read the following blog which explains the differences and synergies.
What role does data warehousing play in the age of in-memory computing?
This question has come up many times since the launch of HANA which led to the ASUG session 'Data Warehousing in the Age of In-Memory Computing and Real-Time Analytics' at SAPPHIRE/ASUG 2014. See copy attached below.
How does S/4HANA, the new Business Suite, impact data warehousing, especially the future of BW?
The answer is pretty much the same as the answer on top of this page in regard to the first question. Thomas Zurek also wrote an excellent short blog about this topic answering this question many customers approached us with since the launch of S/4HANA.
What is SAP's EDW Enterprise Data Warehousing Strategy?
SCN landing page: http://scn.sap.com/docs/DOC-70821
See the following link for the latest short overview of SAP's EDW Positioning.
There is also a new HANA EDW roadmap that outlines the synergy of SAP's data warehousing portfolio around the HANA Platform including BW, Power Designer, HANA EIM, Agile Data Preparation etc.
Also see this very interesting blog about the HANA EDW.
There is also an older presentation from 2013 outlying SAP's going forward considerations about SAP HANA, SAP NetWeaver BW and Sybase IQ. It still provides some valid details about the overall composition of SAP's EDW solution portfolio