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Question

Which one of the following pairs is correctly matched in the context of database design?

List – I                                       List – II
(Database term)                      (Definition)

I. Specialization                       A. Result of taking the union of two or more
disjoint (lower-level) entity sets to produce
a higher-level entity set.
II. Generalization                    B. Express the number of entities to which another
entity can be associated via a relationship set.
III. Aggregation                       C. Result of taking a subset of a higher-level
entity set to form a lower-level entity set.
IV. Mapping cardinalities      D. An abstraction in which relationship sets (along
with their associated entity sets) are treated as
higher-level entity sets, and can participate in
relationships.
Codes :
      I    II   III   IV

a.

D  A   B   C

b.

D  C   B   A

c.

C  D   A   B

d.

C  A   D   B

Answer: (d).C  A   D   B

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Q. Which one of the following pairs is correctly matched in the context of database design? List – I                                       List – II (Database...

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