Define data independence, Database Management System

Data independence seems that "the application is independent of the access strategy and storage structure of data". In other words, the ability to change the schema definition in one level could not change the schema definition in the next higher level. Two kinds of Data Independence:

  • Physical Data Independence: Change in physical level could not affect the logical level.
  • Logical Data Independence: Change in logical level could affect the view level.




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Posted Date: 7/30/2012 1:35:59 AM | Location : United States

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