hi friends,
What do you mean by the term called " Database Anomaly " in the database management systems? Can anyone provide me the information and explanation about the same ?
thanks a lot.....
hi friends,
What do you mean by the term called " Database Anomaly " in the database management systems? Can anyone provide me the information and explanation about the same ?
thanks a lot.....
Database Anomalies
Database anomalies are the problems in relations that occur due to redundancy in the relations. These anomalies affect the process of inserting, deleting and modifying data in the relations. Some important data may be lost if a relation is updated that contains database anomalies. It is important to remove these anomalies in order to perform different processing on the relations without any problem.
Types of Anomalies - Different types of database anomalies are as follows:
- Insertion Anomaly - The insertion anomaly occurs when a new record is inserted in the relation. In this anomaly, the user cannot insert a fact about an entity until he has an additional fact about another entity.
- Deletion Anomaly - The deletion anomaly occurs when a record is deleted from the relation. In this anomaly, the deletion of facts about an entity automatically deleted the fact of another entity.
- Modification Anomaly - The modification anomaly occurs when the record is updated in the relation. In this anomaly, the modification in the value of specific attribute requires modification in all records in which that value occurs.
Database Anomaly is the constraint in database management systems that prevents you from adding/update/delete the specific information/fact until you add/update/delete another information/fact that is required before.
In database anomaly, there is -
- insertion anomaly
- update anomaly
- delete anomaly
Insertion anomaly indicates that we cannot add a data into the relations until another data is added....
As I know database anomalies are the problems in relations that occur due to redundancy in the relations. These anomalies affect the process of inserting, deleting and modifying data in the relations.
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