HI Naveen,
Welcome to SCN.
importance of BW and what is the data base
why we are working on SAP BW.
Star schema--
In business terms, a star schema is a method of organizing information in a data warehouse
that allows the business information to be viewed from many perspectives. A basic star schema
is a multidimensional data model. It is based on a central fact table surrounded by several dimension
tables in the shape of a star (hence the name).The benefits of the basic star schema include:
Flexible solution that can be easily adjusted to changing business requirements
High reporting efficiency
Extended star schema
The BW extended star schema differs from the basic star schema, in case of extended star schema, we will have Fact table connected to the Dimension table and the Dimension table is connected to the SID table and SID table is connected to the master data tables.
please find the link
LEARN SAP BI : Extended Star Schema
Thanks,
Phani.