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Chapter 19 Methodology Monitoring and Tuning the Operational System
Review Questions
19.1 Describe the purpose of the main steps in the physical design methodology presented in this
chapter.
Step 7 of physical database design considers denormalizing the relational schema to improve
performance. There may be circumstances where it may be necessary to accept the loss of
19.2 Under what circumstances would you want to denormalize a logical data model? Use
examples to illustrate your answer.
Generally, if overall performance needs to be improved, controlled redundancy can be introduced
(see also Step 7).
Examples:
If queries on staff always require the branch address, this attribute could be posted into staff.
19.3 What factors can be used to measure efficiency?
19.4 Discuss how the four basic hardware components interact and affect system performance?
19.5 How should you distribute data across disks?
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The basic principles of the distributing the data across disks are (see Figure 19.11):
Exercises
19.6 Investigate whether your DBMS can accommodate the two new requirements for the
DreamHome case study given in Step 8 of this chapter. If feasible, produce a design for the
two requirements and implement them in your target DBMS.