Abstract: Data warehousing and on-line analytical processing (OLAP) are decision support, which has increasingly become a focus of the database industry. Many marketable products and services are now available, and all of the principal database management system vendor now have offerings in these areas. Decision support places some rather different requirements on database technology compare to traditional on-line transaction processing applications. This paper provides an overview of data warehousing and OLAP technologies, with an emphasis on their new requirements. It can be back end tools for extracting, cleaning and loading data into a data warehouse; multidimensional data models typical of OLAP; front end client tools for querying and data analysis; server extensions for proficient query processing; and tools for metadata management and for managing the warehouse.
Keywords: OLAP, Data warehousing, database management system, vendor.