Decision Support Systems are designed to help management monitor key factors in their business operations by accessing business databases. DS Systems might be used in tracking revenue, sales trends, inventory levels and distribution problems, and for doing cost and profitability analyses. Section 3, introduces the terminology necessary to describe the Cascades architecture. Section 5 describes the optimizer framework and the model structure in Cascades. Finally, sections 8 and 9 discuss future work and conclusions, respectively.
Query optimization is introduced in the following section.
Extensible query optimizers are optimizers that allow new features added to a database system to be easily incorporated into the query optimizer. Extensibility is covered in section 4. 2. While six of the 32 queries of the Wisconsin benchmark involve aggregation, no query accesses more than three relations.