4.6 Data Warehouses
DataWarehouses—large historical databases for decision-support that are loaded with new data on a periodic basis — have evolved to require specialized query processing support, and in the next section we survey some of the key features that they tend to require. This topic is relevant for two main reasons:
1. Data warehouses are a very important application of DBMS technology. Some claim that warehouses account for 1/3 of all DBMS activity [26, 63].
2. The conventional query optimization and execution engines discussed so far in this section do not work well on data warehouses. Hence, extensions or modifications are required to achieve good performance.Architecture Of a Database System – Pag 196