Analysis Services (OLAP)
Online Analytical Processing (OLAP) is a business tool that allows an organization to slice and dice their data as they see fit. It doesn't provide day-to-day transaction processing capabilities, otherwise known as Online Transaction Processing (OLTP). That's still provided by the core database engine at the center of a company's software packages.
SQL Server 2000 comes packaged with Analysis Services (known as OLAP Services in SQL Server v7.0), and allows a company to view their data in almost any way they could possibly imagine.
An experienced DBA can set up one or more data cubes and define some relevant business dimensions, such as time, number of items sold, and revenue. A senior manager can then gather an overview of the company's performance over a specified time. But there's nothing so special about that, right? After all, with Microsoft Access you can write reports to generate the same information. With an OLAP cube, however, the manager can drill into each quarter, month, and, if provided, day. So, while a very high level of data can be analyzed, analysis can also be performed on a finer subset of data.
Microsoft has made a number of enhancements to the analysis services inside SQL Server 2000, including the following:
Enhanced security. Allows you to specify a finer grain of control over viewable data.
Integration with Active Directory (AD). You can publish a server (register within AD) so that users can easily locate the server, using Windows search functionality.
Indexed views. Allows you to use views for aggregation instead of tables. This offers much better performance and flexibility.
Relational database data mining. Use the data mining technology to discover information inside a normal RDBMS system, as well as OLAP cubes.
This is just a subset of the enhancements within the analysis services. For a detailed explanation of the features and components, take a look at the SQL Server web site.