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Author Question: What are the roles of aggregation and association in relational database? What will be an ideal ... (Read 25 times)

notis

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on: Jul 7, 2018
What are the roles of aggregation and association in relational database?
 
  What will be an ideal response?

Question 2

Design patterns are usually classified based on the type of the problems that they address.
 
  Indicate whether the statement is true or false


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fraziera112

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Reply #1 on: Jul 7, 2018
Answer to Question 1

To map to a relational database, aggregation must be flattened into association; that is, the relational model is flat: tables do not own each other and are not composed of each other. This means that aggregation and composition relationships must be changed to association to map to tables. The task is not complicated: the table for the aggregate class provides the primary key, the tables for aggregating classes implement the foreign keys, and the multiplicity stays the same.

Answer to Question 2

TRUE


notis

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Reply 2 on: Jul 7, 2018
Excellent

nguyenhoanhat

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Reply 3 on: Yesterday
:D TYSM

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