Data warehouses make the job of a consultant simpler. The data warehouse is generally used in large organizations. It is designed to get data from all the sources in a company and make it available for reporting and analytical software. The data warehouses are denormalized and meant for Online Analytical Processing (OLAP). Some of the leading systems are:

• Terrada
• Netezza
• Vertica
• Actian

The data warehouse helps the consultant to get all the organizational data from one single source. The validation phase also becomes easier in customers have invested in a data warehouse.