First Normal Form (1NF):
The 1NF consider being the first step in normalization process. It focuses on the shape of the records. In this form we need to make sure that each cell has only a single value such as one phone number one product instead of putting two together. Moreover, we must not have a field that contains a number and other field contains a text, all values in each colum has to have only one data type. In addition, the rows have to be uniquely identified if it’s not we have to add a unique ID, or add more column to make it unique.
Second Normal Form (2NF):
In 2NF form we deal with partial dependencies. Which basically means that we can’t reach this form until the table already in the1NF form. In 2NF all non-key attributes are fully functional dependent on the primary key, and for those attributes don’t belong to the dependent key should be transferred to another table, to make sure that all attributes are dependent on a key.
Third Normal Form (3NF):
This form is reached when it is already in 2NF and have the transitive dependencies fixed. Once we have non-keys determine other non-keys, we should remove them from the table and put them in a separate table. to make sure that all fields (columns) can be determined only by the key in the table and no other column.
Boyce-Code Normal Form (BCNF):
This form is reached when we already in 3NF, This form can be called spatial NF3 and have functional dependencies fixed. It is when a non-key determines a part of a composite key. In this form we disallows a non-key attribute functionally determines the part of a composite key.
Fourth Normal Form (4NF):
This form is reached when we are already in BCNF, and there is no existence for the multivalued dependencies (MVDs) in the relation or there are multivalued dependency but the attributes, which are multi value dependent on a specific attribute, are dependent between themselves.
Fifth Normal Form (5NF): This form is reached when we are already in 4NF and has no join dependency. And here it defines a point where a table cannot be decomposed further. 5NF known as (PJ/NF).