Hi Ramya,
According to me the bottom-line of LSA++ is a holistic framework covering different BI requirements. There are basically three flavors:
- EDW Core for standardized template-based BI;
- Agile extension for agile and ad-hoc BI;
- Operational extension for operational data and real-time BI.
The EDW Core can be compared with the classic LSA. Here the goals did not change: reporting on harmonized and consistent data. Also in classic LSA it was certainly not a best practice to store data in every layer which does not add value in most cases. However, depending on the company's data management requirements, you will normally store this kind of data more than once.
The Agile extension is new compared to classic LSA. Centrally managed Agile DataMarts and departmental managed data are covered here.
The Operational extension is new compared to classic LSA. Data can be stored in BW but can also be externally managed.
Furthermore, a difference is indeed an increased usage of virtual objects. Persistent storage is in many cases not necessary and does not add value. You can observe that for the Agile extension and Operational extension.
EDW Core can also benefit from it, you do not need in all cases to store data persistently in all layers. However, you have to be careful here. Every layer in the EDW Core often represents a service level and a step towards harmonized and consolidated data.
A well-balanced LSA++ implementation addresses the three different flavors. It keeps the implementation more transparent, simple and less time-consuming.
Last but not least, please have a look to the document LSA++ for an overview of LSA++.
Best regards,
Sander