Parallel query processing, as described in this chapter, means that the same query is ru...

Parallel query processing, as described in this chapter, means that the same query is run on multiple processors and that each processor accesses in parallel a different subset of the database. Another form of parallel query processing, not discussed in this chapter, would partition the query so that each part of the query runs on a different processor, but that part accesses whatever part of the database it needs. Most queries involve a qualification clause that selects the records of interest in the query. In general, this qualification clause is of the following form:

(condition OR condition OR …) AND (condition OR condition OR . . .) AND . . .

Given this general form, how might a query be broken apart so that each parallel processor handles a subset of the query and then combines the subsets together after each part is processed?

Problems and Exercises 19–22 refer to the large Pine Valley Furniture Company data set provided with the text.