Describe physical data independence, Database Management System

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Describe Physical Data independence ?

Physical Data Independence - It is capacity to modify the internal schema without having to change conceptual schema. Therefore, the external schemas required not be changed as well. Changes to the internal schema might be required because some physical files had to be reorganized to improve the performance of retrieval or update. If the similar data as before remains in the database, the conceptual schema requires not be changed.


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