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d351235422 It supports analytical reporting, structured and/or ad hoc queries and decision making. PDF Version Quick Guide Resources Job Search Discussion . This is to support historical analysis. Figure 1-2 Architecture of a Data Warehouse Description of "Figure 1-2 Architecture of a Data Warehouse" In Figure 1-2, the metadata and raw data of a traditional OLTP system is present, as is an additional type of data, summary data. Using this data warehouse, you can answer questions such as "Who was our best customer for this item last year?" This ability to define a data warehouse by subject matter, sales in this case, makes the data warehouse subject oriented. Previous Page . .. It usually contains historical data derived from transaction data, but can include data from other sources. This tutorial adopts a step-by-step approach to explain all the necessary concepts of data warehousing. The OLTP system stores only historical data as needed to successfully meet the requirements of the current transaction.
Next Page . Three common architectures are: Data Warehouse Architecture (Basic) Data Warehouse Architecture (with a Staging Area) Data Warehouse Architecture (with a Staging Area and Data Marts) Data Warehouse Architecture (Basic) Figure 1-2 shows a simple architecture for a data warehouse. In addition to a relational database, a data warehouse environment can include an extraction, transportation, transformation, and loading (ETL) solution, online analytical processing (OLAP) and data mining capabilities, client analysis tools, and other applications that manage the process of gathering data and delivering it to business users. You can do this programmatically, although most data warehouses use a staging area instead. Figure 1-4 Architecture of a Data Warehouse with a Staging Area and Data Marts Description of "Figure 1-4 Architecture of a Data Warehouse with a Staging Area and Data Marts" Note: Data marts are an important part of many data warehouses, but they are not the focus of this book. For example, a typical data warehouse query is to retrieve something such as August sales. Figure 1-4 illustrates an example where purchasing, sales, and inventories are separated. End users directly access data derived from several source systems through the data warehouse. Nonvolatile Nonvolatile means that, once entered into the data warehouse, data should not change.