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Author Question: What is the purpose of an index? What will be an ideal ... (Read 48 times)

Bernana

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on: Jul 7, 2018
What is the purpose of an index?
 
  What will be an ideal response?

Question 2

What is necessary redundancy in a relational database?
 
  What will be an ideal response?


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Li Jun

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

An index is a mechanism for increasing the speed of data search and data retrieval on relations with a large number of records.

Answer to Question 2

Multiple appearances of foreign key values in the 3NF set of relational tables represent necessary redundancy, which is essential for connecting the tables.


Bernana

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Reply 2 on: Jul 7, 2018
Wow, this really help

at

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Reply 3 on: Yesterday
Gracias!

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