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Author Question: Describe the update cascade option (for implementing a referential integrity constraint). What ... (Read 26 times)

dbose

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on: Jul 7, 2018
Describe the update cascade option (for implementing a referential integrity constraint).
 
  What will be an ideal response?

Question 2

Give a definition of 1NF.
 
  What will be an ideal response?


heinisk01

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

The update cascade option allows the primary key value of a record to be changed if its primary key value is referred to by a foreign key value. However, all the foreign key values that refer to the primary key being changed are also changed and set to the new value of the primary key.

Answer to Question 2

A table is in 1NF if each row is unique and no column in any row contains multiple values from the column's domain.


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