Without normalization, it become difficult to handle and update the database without facing data loss. Insertion , Updation and Deletion Anamolies are very frequent if database is not normalzed. Suppose we have the following table in database .
Update Anamoly :
Suppose if we have to update the address of Ishant from Delhi to Banglore then we will have to update it in every row .
| S_id | S_Name | S_address | Sub_opted |
| 401 | Ishant | Delhi | Algorithm |
| 402 | Gaurav | Noida | Operating System |
| 403 | Aman | Banglore | Data Structure |
| 404 | Ishant | Delhi | Java |
Update Anamoly :
Suppose if we have to update the address of Ishant from Delhi to Banglore then we will have to update it in every row .
Insertion Anamoly :
Suppose for new admission , we have a student id (S_id) , name and addres of a student but if student has not opted for any subjects then we have to insert NULL there , leading to Insertion Anamoly.
Deletion Anamoly :
Suppose if a student (S_id) 401 has only one subjects and temoparily he drops it , when we delete that row then the entire student record will be deleted again along with it .
Deletion Anamoly :
Suppose if a student (S_id) 401 has only one subjects and temoparily he drops it , when we delete that row then the entire student record will be deleted again along with it .
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