OLAP Services provides a scalable OLAP architecture to address a variety of data warehousing scenarios.
Using the Storage Design wizard, you can optimize the trade-off between system performance and disk space allocated to storing aggregations. Microsoft® SQL Server™ OLAP Services uses a sophisticated algorithm to determine the optimum set of aggregations from which other aggregations can be derived. As a result, you can focus on application design issues and leave the complex management of aggregation design up to the system.
You can tune the performance of a cube to provide quick response to the queries most often executed by directing the Usage-Based Optimization wizard to design aggregations appropriate to those queries while maintaining reasonable storage requirements. Thus, you can quickly build a system with a minimum number of aggregations, and then later optimize performance according to the actual usage of the system.
In MOLAP and HOLAP storage modes, OLAP Services stores all or some of the cube information in multidimensional structures. In these structures, storage is not used for empty cells, and a sophisticated data compression algorithm is applied to data that is stored. When combined with the flexible options for the design and optimization of precalculated aggregations, these techniques help to minimize the impact of the “data explosion syndrome” inherent in OLAP technology.
PivotTable® Service incorporates functionality from the server so that calculations can often be performed on the client instead of the server. This spreads the computational load between the server and the client, thus increasing the capacity of the server, reducing network traffic, and improving performance for the clients.
You can spread a cube over multiple servers by dividing it into partitions. OLAP Services can then retrieve data in parallel to answer queries. Partitioning enables you to manage your storage strategy, increase scale with multiple servers, and increase performance.
Note User-defined partitions are available only if you install Microsoft SQL Server OLAP Services, Enterprise Edition.
A cube can be updated by processing only data that has been added rather than the entire cube; you can use incremental update to update OLAP cubes while they are in use.
Intelligent cache management integrates the OLAP server with the PivotTable Service client, minimizing traffic over LAN and WAN connections. PivotTable Service contains an efficient multidimensional calculation engine to further minimize network traffic and to enable analysis of local multidimensional data when the client is not connected to the server.
Microsoft ActiveX® controls, Active Server Page (ASP) scripting, and ActiveX Data Objects (ADO) APIs provide a variety of solutions for querying OLAP data over the Web.
In addition to the Intel® platform, all of the client and server technologies of OLAP Services are supported on Microsoft Windows NT® for the DEC Alpha platform.
PivotTable Service runs on Microsoft Windows® 95 and Windows 98, supporting client applications available for these platforms as well as for Windows NT.