Relational Databases

CHAPTER 4 RELATIONAL DATABASES SUGGESTED ANSWERS TO DISCUSSION QUESTIONS 4.1 Contrast the logical and the physical view of data and discuss why separate views are necessary in database applications. Describe which perspective is most useful for each of the following employees: a programmer, a manager, and an internal auditor. How will understanding logical data structures assist you when designing and using database systems?</para></question><question id="ch04ques02" label="4.2"> Databases are possible because of their database management system (DBMS). As shown in Figure 4.2, the DBMS is a software program that sits between the actual data stored in the system and the application programs that use the data. As shown in Figure 4.4, this allows users to separate the way they view the data (called the logical view) from the way the data is actually stored (the physical view). The DBMS interprets the users ' requests and retrieves, manipulates, or stores the data as needed. The two distinct views separate the applications from the physical information, providing increased flexibility in applications, improved data security, and ease of use. In a database system, the manager will rarely need to understand or be familiar with the physical view of the data. Nor, in most instances, will the internal auditor and the programmer as most everything they do involves the logical view of the data. If accountants understand logical data structures and the logical view of the data, they are better able to manage, use, and audit a database and its data.

4.2 The relational data model represents data as being stored in tables. Spreadsheets are another tool that accountants use to employ a tabular representation of data. What are some similarities and differences in the way these tools use tables? How might an