Schema Translation - Information Systems Reengineering, Integration and Normalization - page 103

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Fig. 3.28 Map PR 2 into EER model

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Fig. 3.29 Map SR 1 into EER model

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Fig. 3.30 Map SR 2 into EER model

example, the SR 1 relational type in the classification table can be mapped to follow-
ing entities and their relationships in Fig. 3.29 .
Substep 5—Map SR 2 into a binary/n-ary relationship.
For each SR 2 relation, define an entity type for each of the KAG type attributes,
with the KAG attribute as its entity key. Define a binary relationship type between
all the entity types defined by the KAP and KAG attributes in the key of this SR 2
relation. The NKA attributes form the attributes of this binary relationship type. If
the key of the SR 2 relationship is part of the primary key of another secondary rela-
tion, then it is mapped as an n-ary relationship in the EER model. For example, the
SR 2 relational type in the classification table can be mapped to the following entities
and their relationships in Fig. 3.30 .
Substep 6—Map each FKA into a relationship