The data warehouse size and query complexity may cause an unacceptable delay in decision support queries. A basic condition for the success of a data warehouse is the capability to supply decision-makers with both precise information and best response time. For this purpose, the concept of indexed views is used. Indexed views help to speed-up query processing and reduce the response time for tracing queries, especially for queries about past histories. Indexed views may significantly by reducing the amount of work that SQL Server to return the required data and im- prove query performance and solve the problem of decision support workloads. this article is applicable to data warehouse de-signed by using SQL Server. It is not applicable if the data warehouse was designed by using another software like Oracle, DB2 and Informix. For many years, Mi- Microsoft SQL Server has supported the ability to create virtual tables known as views.