Big Data, Data Warehouses, and Business Intelligence Systems - Database Processing: Fundamentals, Design, and Implementation - page 559

The City = San
Antonio data are
also showing customer
data
The Customer =
Able, Ralph data are
also showing year
data
Figure 12-22
OLAP ProductNumber by
City, Customer, and Year
Report
The city variable is
on the column
designator
The ProductID
variable is on the
primary row designator
The ProductID =
VB001 data are also
showing Customer
data
The Customer =
Able, Ralph data are
also showing year
data
Figure 12-23
OLAP City by
ProductNumber, Customer,
and Year Report
Accordingly, special-purpose products called OLAP servers have been developed to per-
form OLAP analyses. As shown in Figure 12-24, an OLAP server reads data from an operational
database, performs preliminary calculations, and stores the results of those calculations in
an OLAP database. For performance and security reasons, the OLAP server and the DBMS
usually run on separate computers. The OLAP server would normally be located in the data
warehouse or a data mart.