Typically, analytical databases comprise two main components: a data warehouse and an online analytical processing
(OLAP) front end. The data warehouse is a specialized database that stores data in a format optimized for decision
support. The data warehouse contains historical data obtained from the operational databases as well as data from
other external sources. Online analytical processing (OLAP) is a set of tools that work together to provide an
advanced data analysis environment for retrieving, processing, and modeling data from the data warehouse. In recent
times, this area of database application has grown in importance and usage, to the point that it has evolved into its own
discipline: business intelligence. The term business intelligence describes a comprehensive approach to capture and
process business data with the purpose of generating information to support business decision making. Chapter 13,
Business Intelligence and Data Warehouses, covers this topic in detail.