Normalization (1 NF )
We saw the anomalies that could sweep in a design, making to a bad data base design. Let’s see what we can do to avoid them or at least reduce the chances.
There are Normal forms ranging from 1 NF to 5 NF ensuring higher safety levels.
First rule: Every table has to have a Primary Key.
Primary Key would imply that the column or columns that form the Primary Key can’t have any NULL value across any of its records and all values are unique.
Multiple columns together can be assigned a Primary Key.
Second rule: In a column, don’t keep mixed info.
Ex: Don’t keep Birth Date and Name just in one column together.
Third Rule: Don’t repeat the same type of info groups.
Ex: Ram got 5 $, 10 € and 500 ₹.
Currency is repeating in every row and violates the 1 NF rule.
How do we make it comply with 1 NF?
Let’s examine 2 NF to 5 NF the next time!
Written by: Piyush Kulkarni
