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Logical data independence means that users are shielded from changes in the logical structure of the data, i.e., changes in the choice of relations to be stored.

For example, if a relation Students(sid, sname, gpa) is replaced by Studentnames(sid, sname) and Studentgpas(sid, gpa) for some reason, application programs that operate on the Students relation can be shielded from this change by defining a view Students( sid, sname, gpa) (as the natural join of Studentnames and Studentgpas). Thus, application programs that refer to Students need not be changed when the relation Students is replaced by the other two relations. The only change is that instead of storing Students tuples, these tuples are computed as needed by using the view definition; this is transparent to the application program.

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