Database Design for Mere Mortals®: A Hands-on Guide to Relational Database Design, Third Edition

8. Keys

A fact in itself is nothing. It is valuable only for the idea attached to it, or for the proof which it furnishes.

—CLAUDE BERNARD

Topics Covered in This Chapter

Why Keys Are Important

Establishing Keys for Each Table

Table-Level Integrity

Reviewing the Initial Table Structures

Case Study

Summary

Review Questions

By now you’ve identified all the subjects that the database will track and defined the table structures that will represent those subjects. Furthermore, you’ve put the structures through a screening process to control their makeup and quality. In this next stage of the database design process, you’ll begin the task of assigning keys to each table. You’ll soon learn that there are different types of keys, and each plays a particular ...