Use of Extended E-R Features

Posted By on October 3, 2014


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Use of Entity or Relationship Sets
Design of an E-R Database Scheme

Use of Extended E-R Features

We have seen weak entity sets, generalization and aggregation. Designers must decide when these features are appropriate.

  • Strong entity sets and their dependent weak entity sets may be regarded as a single “object” in the database, as weak entities are existence-dependent on a strong entity.
  • It is possible to treat an aggregated entity set as a single unit without concern for its inner structure details.
  • Generalization contributes to modularity by allowing common attributes of similar entity sets to be represented in one place in an E-R diagram.

Excessive use of the features can introduce unnecessary complexity into the design.

Use of Entity or Relationship Sets
Design of an E-R Database Scheme

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Posted by Akash Kurup

Founder and C.E.O, World4Engineers Educationist and Entrepreneur by passion. Orator and blogger by hobby

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