Question

What are the various anomalies when a table is said to be in INF? How they can be overcome?​

Answer 1

Answer:

Normalization in DBMS: 1NF, 2NF, 3NF and BCNF in Database

BY CHAITANYA SINGH | FILED UNDER: DBMS

Normalization is a process of organizing the data in database to avoid data redundancy, insertion anomaly, update anomaly & deletion anomaly. Let’s discuss about anomalies first then we will discuss normal forms with examples.

Anomalies in DBMS

There are three types of anomalies that occur when the database is not normalized. These are – Insertion, update and deletion anomaly. Let’s take an example to understand this.

Example: Suppose a manufacturing company stores the employee details in a table named employee that has four attributes: emp_id for storing employee’s id, emp_name for storing employee’s name, emp_address for storing employee’s address and emp_dept for storing the department details in which the employee works. At some point of time the table looks like this:

emp_id emp_name emp_address emp_dept

101 Rick Delhi D001

101 Rick Delhi D002

123 Maggie Agra D890

166 Glenn Chennai D900

166 Glenn Chennai D004

Explanation: