Author Question: Copies of each database record or page before being changed by a transaction that are saved for use ... (Read 66 times)

laurencescou

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Copies of each database record or page before being changed by a transaction that are saved for use in database recovery are called before images.
 
  Indicate whether the statement is true or false

Question 2

Describe the steps in assessing table structure when you are given a set of tables and asked to construct a new database to store the existing data.
 
  What will be an ideal response?



blakcmamba

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Answer to Question 1

TRUE

Answer to Question 2

First, you should count the number of rows in the tables and determine the type of data stored in each column. Second, you should analyze the existing data values and work with users to determine (1 ) multivalued dependencies, (2 ) functional dependencies, (3 ) candidate keys, (4 ) primary keys and (5 ) foreign keys. Finally, you should check the validity of the possible referential integrity constraints.



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