Schemas Integration - Information Systems Reengineering, Integration and Normalization - page 267

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Fig. 7.5 EER model with weak entity conflict

another schema, but with an additional key component from its strong entity. The
former dominates the latter. Hence, weak entity overrides the strong entity by trans-
forming the strong entity to weak entity for consistency. This translation process is
bidirectional and information capacity equivalent (Fig. 7.5 ).

Substep 1.6. Resolve conflicts on subtype entities.
Conflict exists where a subtype entity appears as a super type entity in another
schema. The verification of this step is to identify the overlapping of two identical
entities in bidirectional in two different schemas. A1 is-a A2 in one schema and A2
is-a A1 in another schema. This translation process is transformed into schema with
1:1 cardinality (Fig. 7.6 ).

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