Database Reference
In-Depth Information
2.
Use a field (or set of fields) from the
original
table to relate the original table to
the new table; try to select fields that represent the subject of the table as closely as
possible. The field(s) you choose will appear in both tables. (You'll learn more
about relating tables in
Chapter 10
.)
3.
Assign an appropriate name, type, and description to the new table and add it to
the Final Table List.
These steps form a generic procedure that youcan use to resolve any multivalued field you
encounter in a table. Now, apply these steps to the C
ATEGORIES
T
AUGHT
field.
1.
Remove the field from the INSTRUCTORS table and use it as the basis of a new
table. Because this will now be a
single
-valued field, rename the field C
ATEGORY
T
AUGHT
.
2.
Use I
NST
F
IRST
N
AME
and I
NST
L
AST
N
AME
as the connecting fields that will relate
the INSTRUCTORS table to the new table, and add them to the structure of the
new table.
3.
Give the new table a proper name, compose a suitable description, and add the
table to the Final Table List. (Indicate the table's type as “Data.”) Here's one pos-
sible name and description you might use for the new table:
Instructor Categories—the categories of software programs that
an instructor is qualified to teach. The information this table
provides allows us to make certain that there is an adequate num-
ber of instructors for each software category.
Figure 7.20
shows the revised INSTRUCTORS table and the new INSTRUCTOR
CATEGORIES table.
