Anomalies.

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Inconsistency present in database that will lead to incorrect value in Database is called Anomalies.
In database following anomalies are happen like insertion, deletion and updates anomalies.

Note: 
1. Null are allowed only in case of parent or child value.
2. Redundancy( Repetition which can not be avoided).

Example:-  Table showing different anomalies.
Insertion Anomalies: Insertion is leaving NULL value in table is called Insertion anomalies.
Example shown in above table where insertion leave f_name of EMP_ID number 103.

Updation Anomalies: Updation of a value leads to inconsistency in table is called Updation anomalies.


Deletion Anomalies: If deletion from table leads to loss of information is called Deletion Anomalies.
If we delete the information of emp_id 102 then dep_id 23's information loss. 

Note:- To avoid anomalies of table we perform normalization of table with different rule such as 1NF, 2NF, 3NF AND BCNF.

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