The need for an effective information management solution is of top priority in today’s changing & competitive business environment. Various Information systems like OLTP systems, DSS& EIS has been serving this information management need for many years. Data warehousing is an Enhancement of such information management solutions in providing complete, integrated enterprise a information management solution which highly supports business strategic decision making & information management. Data warehousing techniques has been experimented & implemented with success by many enterprises over the past two decades. Data warehousing technology is currently hottest in today’s the topic enterprise information management. Companies reap their benefits from Data warehouses in the long run.