New Challenges in Physical
In this chapter we discuss some future directions and challenges in the area of
physical database design. Some of the problems we introduce in the following
sections have been partially addressed in the recent literature, while others
remain fairly open-ended. Figure 12.1 depicts a high-level architecture of a
traditional physical design tool and introduces the four challenges that we
cover in subsequent sections. Specifically, we discuss the ability to (1) handle
richer workloads, (2) make additional recommendations related to physical de-
sign, (3) interact with physical design tools in different ways, and (4) evaluate
competing physical design algorithms in a principled manner.
12.1 Leveraging Richer Workloads
Different formulations of the physical design problem assume that the work-
load consists of a set (or sequence) of Standard Query Language ( SQL ) state-
ments. While this is actually the case in the majority of scenarios, there are
still some special cases and extensions that deserve further analysis. In this
section we discuss some challenges in workload modeling.
12.1.1 Parametric Workloads
Some common workloads contain queries that repeat over time with slight
variations. For instance, the following query attempts to obtain the total U.S.
sales that were made in the (current) month of March 2010: