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Author Question: Which of the following is not true about representing subtypes in a relational database design? ... (Read 18 times)

craiczarry

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on: Jul 7, 2018
Which of the following is not true about representing subtypes in a relational database design?
 
  A) One table is created for the supertype and one for each subtype.
  B) All of the attributes of the supertype are added to the subtype relations.
  C) The key of the supertype is made the key of the subtypes.
  D) An instance of the supertype may be related to one instance each of several subtypes.

Question 2

When running an SQL query that uses NOT EXISTS, the NOT EXISTS keyword will be true if ________.
 
  A) any row in the subquery meets the condition
  B) all rows in the subquery meet the condition
  C) no row in the subquery meets the condition
  D) any row in the subquery fails to meet the condition


Jody Vaughn

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

B

Answer to Question 2

C


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