It is the main depot of an organization’s historical data and its corporate memory, containing the raw material for the decision support system of management. What lead to the use of data warehousing is that it allows a data analyst to execute complex queried and analyses like data mining on the info without making any slow in an operational system. The collection of data in Data warehousing is planned for supporting the decision making of the management. These warehouses contain an array of data presenting a coherent image of business conditions in time at a single point. Data Warehousing is a repository of information that is available for analysis and query.
