Data warehouses

DATAWAREHOUSES Data Warehouses Affiliation A data warehouse is a large size database in which data is collected from a wide variety of sources. The basic purpose of this database to provide a support for query and analysis instead of transaction processing. Additionally, a data warehouse contains past data which is retreived from processing transaction data, however it combine data coming from a variety of sources. Another most important function of data warehouse is that it establishes a boundary between analysis workload from transaction capacity and allows a firm to combine data from different sources. Moreover, this huge collection of data is based on a relational database, which carries out different functions such as data extraction, transportation, transformation, and loading (ETL) solution, an online analytical processing (OLAP) engine, client analysis tools, and other applications that manage the process of gathering data and delivering it to business users (Oracle, 2002).