Update anomaly-data redundancy, Database Management System

Update Anomaly: This anomaly is occurred due to data redundancy. Redundant information makes updates more complex since, for example, varying the name of the instructor of MCS-014 would need that all tuples having MCS-014 enrolment information be updated. If for some reason, all tuples are not updated, we may have a database that gives 2 names of instructor for the subject MCS-014 which is inconsistent information. This problem is known as update anomaly. An update anomaly results in data inconsistency.

 

Posted Date: 3/7/2013 1:42:24 AM | Location : United States






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