All, thank you for all your comments. Sanjarani, for learning SSAS my book is not the right one. My book is about building a data warehouse and BI, so the coverage on SSAS is very limited. To learn SSAS, it is better to read 2008 books rather than 2005 ones, because of the improvements in SSAS 2008. Irina Gorbach, Edward Melomed and Alexander Berger are reknown expert in SSAS and I'm grateful that they spared their time writing a good SSAS 2008 book (0672330016), which I enjoyed a lot. Another good SSAS book is Sivakumar Harinath and Robert Zare's (0470247983). Although it is in 2005, Teo Lachev's book (0976635305) is extremely structured, and will be a great help to anybody starting SSAS journey.

vchintapanti, to automatically process (refresh) the cube when new data is added in the data warehouse, we can either use a ROLAP partition, or use ProActive Caching. http://msdn.microsoft.com/en-us/library/ms174769.aspx explains the considerations.