A data warehouse is a relationaldatabase that is designed for queryand analysis rather than fortransaction processing. It usuallycontains historical data derived fromtransaction data, but can include datafrom other sourcesData warehouses separate analysisworkload from transaction workloadand enable an organization toconsolidate data from severalsources.In addition to a relational database, adata warehouse environment caninclude anextraction, transportation, transformation, and loading (ETL)solution, online analytical processing(OLAP) and data miningcapabilities, client analysis tools, andother applications that manage theprocess of gathering data anddelivering it to business users
These terms are used as follows Subject Oriented: The data in the data warehouse is organized so that all the data elements relating to the same real - world event or object are linked together. Integrated: Though the data in the data warehouses is scattered around different tables, databases or even servers but the data is integrated consistently in the values of variables, naming conventions and physical data definitions. Nonvolatile: Data in the data warehouse is never over-written or deleted - once committed, the data is static, read - only, and retained for future reporting. Time – variant: The changes to the data in the data warehouse are tracked and recorded so that reports can be produced showing changes over time.
A data warehouse must develop a process to collect the pure raw materialsand then continually repackage them to serve evolving business initiatives.Data warehouses must be built, managed, and delivered. We do not want tochange the technology so it’s important to get it right. A long feature set is not beneficial if development is onerous and cycleturnaround times are long and costly.Each new initiative that a data warehouse serves should be treated as aproject within a program.The data warehouse process is an information product process. We mustestablish the guiding principles and champion, architect, deliver, and supportiterations.The data warehouse engine is the company’s information factory and itshould have high reliability.
Microsoft SQL Server 2005 provides amanageable, scalable data warehouse platform.With several enhancements in SQL Server2005, Microsoft enables Information Technologydepartments to productively manaSge theirgrowing data volumes along with the rapidincrease in usage of the data warehouse. SQL Server database management system Accessible techniques to manage deployment Delivering a data warehouse Interactive data access SQL Server Analysis Services Reporting Services
Through the technology underlying the Microsoft DataWarehousing Framework and the remarkable progress inMicrosoft SQL Server 7.0, Microsoft is working to reducecomplexity, improve integration, and lower costsassociated with storage data.Customers investing in data storage technology based onMicrosoft can be assured that they are creatingapplications with the best possible economicconsiderations, while maintaining full scalability andreliability of their systems.