Database Reference
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Figure 10.18. Incorporating C LASS ID fields within the STUDENTS table structure
Dothese structures look(vaguely)familiar? Theyshould.Byusingthismethod,allyou've
done is to introduce a “flattened” multivalued field into the table structure. In doing so,
you've also introduced the problems associated with a multivalued field. (If necessary, re-
view Chapter 7 , Establishing Table Structures .”) Although you know how to resolve a
multivalued field, this is not a good or proper way to establish the relationship.
The second method you might attempt to use is simply a variation of the first method. In
this case, you take one or more fields from one table and incorporate a single instance
of each field within the other table. For example, you could take the C LASS ID, C LASS
N AME , and I NSTRUCTOR ID fields from the CLASSES table and incorporate them into the
STUDENTS table in order to identify the classes in which a student is currently enrolled.
This may seem to be a distinct improvement over the first method, but you'll see that there
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