
Redundant vs duplicated data
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As we have seen, a major advantage of the database approach is that inconsistency can
be reduced by eliminating redundant data. Also, it seems likely that the elimination of
redundancy will lead to a simpler conceptual model which more accurately reflects the
real world. This chapter gives a fairly informal introduction to the identification and
elimination of redundant data.
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Care must be taken to distinguish between duplicated data and redundant data.
Duplicated data is present when an attribute has two (or more) identical values. A data
value is redundant if you can delete ...