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Author Question: Explain the term time-variant in the following data warehouse definition:The data warehouse is a ... (Read 193 times)

kwoodring

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Explain the term time-variant in the following data warehouse definition:The data warehouse is a structured repository of integrated, subject-oriented, enterprise-wide, historical, and time-variant data.
 
  The purpose of the data warehouse is the retrieval of analytical information. A data warehouse can store detailed and/or summarized data.

Question 2

Table ENROLLMENT is:
 
  A) Not in 1NF
  B) In 1NF but not in 2NF
  C) In 2NF but not in 3NF
  D) In 3NF



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nmyers

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Answer to Question 1

The term time-variant refers to the fact that a data warehouse contains slices or snapshots of data from different periods of time across its time horizon. With these data slices, the user can create reports for various periods of time within the time horizon. For example, if the subject of analysis is cost and the time horizon is a number of years, we can analyze and compare the cost for the first quarter from a year ago versus the cost for the first quarter from two years ago.

Answer to Question 2

C





 

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