by This article describes about normalization. Summary of the article:
- What is Normalization?
- Types of Normalization
- First Normal Form
- Second Normal Form
- Third Normal Form
- Advantages of Normalization
- Disadvantages of Normalization
What is Normalization?
Normalization is a process to remove data redundancy from the database.
Types of Normalization
Following are the types of Normalization.
- First Normal Form
- Second Normal Form
- Third Normal Form
First Normal Form
Data is divided in a small part named table. Each table has unique primary key. Here all data are dependent on primary key.
Second Normal Form
In second normal form all the data are bring together whiches are light primary key independent.
Third Normal Form
In third normal form all the data are bring together whiches are are not dependent on primary key.
Advantages of Normalization
Following are the advantages of normalization:
- Searching, sorting, and creating indexes is faster
- Reduce data redundancy
- More tables allow better use of segments to control physical placement of data
- You usually have fewer indexes per table, so data modification commands are faster
- Fewer null values and less redundant data, making your database more compact
Disadvantages of Normalization
Following are the disadvantages of normalization:
- Requires much more CPU, memory, and I/O to process normalized data
- Requires more joins to get the desired result
- A poorly-written query can bring the database down
- Maintenance overhead. The higher the level of normalization, the greater the number of tables in the database
That’s all about normalization.
