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Fig. 7.3
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Substep 1.4. Resolve conflicts on cardinality.
Conflict exists where identical entities are of different cardinality in two sche-
mas. The verification of this step is subject to the schema that has higher cardinality.
Schema with higher cardinality naturally dominates the other schema with identical
entities. Hence, higher cardinality will override the lower cardinality conflicts. This
translation process is therefore information capacity equivalent and is bidirectional
with feasible recovery of original schema from transformed schema (Fig.
7.4
).
Substep 1.5. Resolve conflicts on weak entities.
Conflict occurs when a strong entity appears as a weak entity in another schema.
The verification of this resolution step is subject to the interdependence between
entities. The schema has a weak entity that is similar to another strong entity in
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