Database Reference
In-Depth Information
7. Establishing Table Structures
It is a capital mistake to theorize before one has data.
—S
HERLOCK
H
OLMES
,
T
HE
A
DVENTURES OF
S
HERLOCK
H
OLMES
Topics Covered in This Chapter
Organizationsusedatabasestokeeptrackofvarioussubjectsthatareimportanttothem.For
example, a medical clinic keeps track of, among other things, its patients, doctors, and ap-
pointments; an equipment rental business must maintain data on its customers, equipment,
and rental agreements; and a registrar's office is concerned (at the very least) with students,
teaching staff, and courses. In every case—and in any other scenario you can imagine—a
table within the database represents each subject. Furthermore, each table is composed of
fields,
which represent the characteristics that define or describe the subject of the table.
Tables constitute the very foundation of the database, and they guarantee a solid and sound
foundation when they are properly designed.
Defining the Preliminary Table List
During this portion of the database design process, you'll define a
Preliminary Table List
that you'll use to identify and establish the tables for the new database. You'll use three pro-
cedures to develop this list. The first involves using the
Preliminary Field List,
the second
involvesusingthe
list of subjects
yougatheredduringtheinterviewingprocess,andthethird
involves using the
mission objectives
you defined at the beginning of the database design
process. You'll then move on to build the structure of each table using fields from the Pre-
liminary Field List.
