The Normal Forms
The database community sets the few rules or guidelines for database normalization. These rules are called as normal forms and starts from the first normal form till the fifth normal form. In this tutorial, we will only discussed about the most essential normal form such as 1NF, 2NF and 3NF.
First Normal Form (1NF)
The first normal form (1NF) sets the very crucial rule to create the database :
1. There are no repeating or duplicate fields.
2. Each cell contains only a single value.
3. Each record is unique and identified by primary key.
The normalization process involves getting our data to adjust in a progressive normal forms and you cannot achieve the higher level of normalization without satisfying the previous levels. The First Normal Form asking the values in each cell of a table must be atomic. The word atomic describes that there should be no sets of values in one particular cell.
Let's see the example below :
Prior to Normalization
| Item | Colors | Price | Tax |
| Pen | red, blue | 2.0 | 0.20 |
| Scale | red, yellow | 2.0 | 0.20 |
| Pen | red, blue | 2.0 | 0.20 |
| Bag | blue, black | 150.00 | 7.80 |
This table is not in first normal form because :
A. There are multiple fields in color lab.
B. Records are repeating (Duplicate records) or no primary key.
First Normal Form (1NF)
| Item | Colors | Price | Tax |
| Pen | red | 2.0 | 0.20 |
| Pen | blue | 2.0 | 0.20 |
| Scale | red | 2.0 | 0.20 |
| Scale | yellow | 2.0 | 0.20 |
| Bag | blue | 150.00 | 7.80 |
| Bag | black | 150.00 | 7.80 |
This table is now in first normal form.
In the next section, we will take a look on the Second form of Normalization.
If you are facing any programming issue, such as compilation errors or not able to find the code you are looking for.
Ask your questions, our development team will try to give answers to your questions.
Ask Questions? Discuss: The Normal Forms View All Comments
Post your Comment