Medium to Large size organizations daily generate a large volume of transactional data. Bigger the size of the organization, more the chances of inaccuracy. That is, there will be repetition of data - contradictory data across various sections of the organization. Data from transactional data is transferred to a Data Warehouse on regular intervals. This data is cleansed, and restructured by providing more indexing which will be helpful to answer to user queries. Normally Business intelligence solutions is derived from such Data Warehouses, which contains crystal clear data. In a large organization Data Warehouse will be the consolidated form of data from various sections of the concern. Data Warehouse comprises of Data Marts which deals with single divisions within the organization. We are capable to build Data Warehouses which will be main repository from which useful Business Intelligence outputs are extracted.