HP Integrity NonStop J-Series User Manual

Page 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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