“A data warehouse is a central repository for all or significant parts of the data that an enterprise’s various business systems collect” (Li ping et al, 2011).
The concept of datawharehouse allows user to have information centrally available without having t worry about which source system provides the source data.
Analysis of this data is typically more performant as in the source systems as in a data warehouse data access is optimized for reporting purposes. This is the case for example for Sap BW, in which data was traditionally stored in Infocubes.
The latest products offered by Sap (BW on Hana and BW / 4 Hana) do use “in-memory” technology, improving further the data load and the reporting performance.
The writer works as Sap BW consultant since its first release. After all those years of implementation one remark, which is not technical, but organizational, is that the datawarehouse is often considerer an non-critical system, as the transaction activity of the organization is performed in the ERP system.
Reporting performance plays an important role for the information consumer.
For IT managers the options available are to continue using the transactional environment for reporting as well, OR, to invest in a data warehouse. Performance optimization in transactional system must for of all focus on the operations performance safety and availability.
The technology used plays a secondary role, in the study (LI Ping, 2011) describes the technical solution : “Establish a connection: Create Open Database Connectivity (ODBC) using a Microsoft SQL Analysis server data source connection; i.e., the Microsoft SQL Server connection.”
It is the concept of datawharehouse which makes the difference when compared to traditional source system reporting.
Bill Inmon was asked by (Erickson, 2006):
“One company has a data warehouse, one company doesn’t-
What are the different information capabilities of these two companies?”
The second major case is speed of Information. Once the data warehouse is built, tbe abilit)’ to get tbe information quickly in the hands of the riglit person in tbe corporation is greatly facilitated
The second major case is speed of Information.”
In the information delivery it is important to consider the audience and the timing in order to optimize the feedback of the provided information.
Modern data warehouses also offer the opporturtunity to “Broadcast” Information targeting specific users with the result of predetermined queries.
Another concept explained in by Inmon (Ericskon, 2006) is that in a data warehouse data can be re-used for many “application” purposes:
“The truth is, to build a data warebouse successfully, you need to free it from the bound- aries of any one given application”.
This can be achieved by preserving the data as delivered by source systems and by constructing “upper” layers of data containing business logics. Whenever those logic change, it is possible to preserve the information delivered by both old and new logics. Often managers coming from other organizations bring a different “vision” on data. Data warehouses do offer the option to represent data with different “visions”.
References
LI, Ping; WU, Tao; CHEN, Mu; ZHOU, Bin; XU, Wei-guo: A study on building data warehouse of hospital information system, Chinese Medical Journal, Issue: Volume 124(15), August 2011, p 2372-2377
Erickson, Jim, DM Review (Interview to Bill Inmon). Jun2006, Vol. 16 Issue 6, p10-13. 4p.
Alessandro Filippi 