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Author Question: Deleting tables and relationships is basically a matter of dropping foreign key constraints and then ... (Read 61 times)

evelyn o bentley

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on: Jul 7, 2018
Deleting tables and relationships is basically a matter of dropping foreign key constraints and then dropping the tables.
 
  Indicate whether the statement is true or false

Question 2

Explain the relationships among primary keys and functional dependencies.
 
  What will be an ideal response?


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lkanara2

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

TRUE

Answer to Question 2

Relations store instances of functional dependencies in their rows. All primary keys represent a functional dependency, since each primary key functionally determines the entire row. Since the primary key determines the entire row, if a primary key were duplicated in a relation, then the entire row would have to be duplicated. Since a relation can contain no duplicate rows, the primary key must be unique.


evelyn o bentley

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Reply 2 on: Jul 7, 2018
Great answer, keep it coming :)

flexer1n1

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Reply 3 on: Yesterday
Wow, this really help

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