8 - Business Intelligence

Abstract

This chapter provides an overview of business intelligence. The database tools found under the heading of business intelligence include data warehousing, online analytical processing (OLAP), and data mining. The functionalities of these tools are complementary and interrelated. Data warehousing provides for the efficient storage, maintenance, and retrieval of historical data. OLAP is a service that provides quick answers to ad hoc queries against the data warehouse. Data mining algorithms find patterns in the data and report models back to the user. All three tools are related to the way data in a data warehouse are logically organized, and performance is highly sensitive to the database design techniques used. A data warehouse is a large repository of historical data that can be integrated for decision support. The use of a data warehouse is markedly different from the use of operational systems. Operational systems contain the data required for the day-to-day operations of an organization. This operational data tends to change quickly and constantly. The table sizes in operational systems are kept manageably small by periodically purging old data. The data warehouse, by contrast, periodically receives historical data in batches, and grows over time.