Hp Integrity NonStop J-Series Manual de usuario Pagina 57

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DEVELOPING A DATA BASE
Drawing the Relationship Between Classes of Information
Sample Data for Dependents
empnum
0001
0002
0004
•••
dependent-name
•••
Jane Jones
Bill Jones
Mark Jones
Judy Martin
Leslie Monte
David Monte
Sue Monte
relationship
S
C
C
C
S
C
C
•••
dependent-age
•••
33
12
10
17
27
3
2
Figure 3-5. Dependents Class with Repeating Data
You can remove this repeating data from the dependents class by
using a technique called "normalization." To normalize the
dependents data, you could include "empnum" with each occurrence
of "dependent-name," "relationship," and "dependent-age." Figure
3-6 illustrates how the sample dependent data appears when you
eliminate repeating data.
3-6
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