I suggest you to read the following blogs by Mahesh Kumar CV
They are very informative and helpful:
http://scn.sap.com/community/developer-center/hana/blog/2013/04/26/big-data-for-starters
http://scn.sap.com/community/hana-in-memory/blog/2013/04/30/big-data-technologies-applications
http://scn.sap.com/community/developer-center/hana/blog/2013/05/20/sap-hana--hadoop-integration-1
http://scn.sap.com/community/developer-center/hana/blog/2013/05/20/sap-hana--hadoop-integration-2