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Virtual Gate Test Series: Databases - Aggregation

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Which of the following is not true?

  1. Generalization is the result of taking the union of two or more disjoint entity sets to produce a higher level entity set.
  2. Specialization is an abstraction in which relationship sets are treated as higher-level entity sets.
  3. Canonical covers are used to decompose a relation into $\text{3NF,}$ which is a small relaxation of the $\text{BCNF}$ condition.
  4. The concurrency control management component of the database is responsible for handling the concurrency control policies.
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B is not true. It is a definition of aggregation

Aggregation is an abstraction in which relationship sets are treated as a higher level entity.
Specilaization is the result of taking a subset of a higher level entity sets a lower level entity sets. 

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