And those interested in smaller warehouses, known as data marts, can use tools from companies such as IBM and Microsoft to create simple applications quickly and inexpensively. All sizes of data warehousing projects can run over budget and fail to meet objectives unless thought out carefully. Agencies must outline clear objectives and anticipate rapid expansion by reserving adequate storage capacity and skilled personnel. Experts recommend starting with small, manageable applications. Initially, don't put anything critical on the warehouse and don't turn it loose to everybody.
Security is another consideration, as is maintenance.
As executives dream up new applications, warehouse staffers must maintain the ability to integrate data from multiple sources. But a newly formed consortium of vendors, known as the Metadata Coalition, is hoping to solve problems associated with the integration of software tools. Possibly the most daunting obstacles to data warehousing are the cultural problems that result during the building phase. Some employees may put up resistance to reengineering required before warehouse construction. Others may raise questions about which departments own data.