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Rule 7
If in rule 1 multivalued attributes are encountered, they are transformed into separate relational schemes according to this rule.
Definition rule 7
Define for each multivalued attribute A a new relational scheme
R' which also contains this attribute A and the primary key of the according
relational scheme R. Together they form the primary key for R'.
In this example you can see the application
of rule 7:
A new relational scheme is created for the multivalued
attribute TelNo containing TelNo as attribute:
ChiefTelNo(TelNo)
The primary key of this multivalued attribute
connected to the relational scheme is used as foreign key in the new scheme:
ChiefTelNo(ChiefEditor_PersNo,
TelNo)
The foreign key and the attribute together form the primary
key for this new relational scheme:
ChiefTelNo( ChiefEditor_PersNo, TelNo)
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