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Author Question: What are the rules for naming and defining attributes? What will be an ideal ... (Read 47 times)

daltonest1984

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on: Jul 7, 2018
What are the rules for naming and defining attributes?
 
  What will be an ideal response?

Question 2

A ________ is an attribute that appears as a non-primary key attribute in one relation and as a primary key attribute (or part of a primary key) in another relation.
 
  A) Referential integrity
  B) Primary key
  C) Foreign key
  D) Unique key


Sassygurl126

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

Name attributes using the following guidelines:
 An attribute name is a noun.
 An attribute name should be unique.
 To make an attribute name unique and for clarity, each attribute name should follow a standard format.
 Similar attributes of different entity types should use similar but distinguishing names.
 An attribute definition states what the attribute is and possibly why it is important.
 An attribute definition should make it clear what is included and what is not included in the attribute's value.
 Any aliases, or alternative names, for the attribute can be specified in the definition.
 It may also be desirable to state in the definition the source of values for the attribute.
 An attribute definition should indicate if a value for the attribute is required or optional.
 An attribute definition may indicate if a value for the attribute may change once a value is provided and before the entity instance is deleted.
 An attribute definition may also indicate any relationships that attribute has with other attributes.

Answer to Question 2

C


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