A) weak entities can be deleted automatically when their strong entity is deleted.
B) Weak entity set avoids the data duplication and consequent possible inconsistencies caused by the duplicating the key of strong entity.
C)A weak entity set has no primary keys unless attributes of the strong entity set on which it depends are included.
D)Tuples in a weak entity set are not partitioned according to their relationship with tuples in a strong entity set.
Answer D.
B) Weak entity set avoids the data duplication and consequent possible inconsistencies caused by the duplicating the key of strong entity.
C)A weak entity set has no primary keys unless attributes of the strong entity set on which it depends are included.
D)Tuples in a weak entity set are not partitioned according to their relationship with tuples in a strong entity set.
Answer D.
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