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Author Question: An artificial column added to a relation to serve as the primary key is a ________. A) composite ... (Read 63 times)

scienceeasy

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on: Jul 7, 2018
An artificial column added to a relation to serve as the primary key is a ________.
 
  A) composite key
  B) candidate key
  C) foreign key
  D) surrogate key

Question 2

Which of the following is not a good reason for designing a data model?
 
  A) It's easier to change things in the data model than it is in the actual DBMS.
  B) The data model provides a simplified view of the database that can be shown to people who don't need to see all the details.
  C) Creating a data model will help you understand the application area better.
  D) The data model can be discarded after the database is operational.


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fromAlphatoOmega22

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

D

Answer to Question 2

D


scienceeasy

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Reply 2 on: Jul 7, 2018
Excellent

mammy1697

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Reply 3 on: Yesterday
Great answer, keep it coming :)

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