Premium Essay

Normalization in Databases

In: Computers and Technology

Submitted By vkrailind
Words 1576
Pages 7
Contents
1- Introduction
2- Why to Normalize?
3- Normalization & Its types.
4- Applications of Normalization.
5- Conclusion

Introduction
While working with databases, one must have got chances to hear the term normalization. If someone asks "Is that database normalized?" or "Is that in BCNF?" All too often, the reply is "Uh, yeah." Normalization is often brushed aside as a luxury that only academics have time for. However, knowing the principles of normalization and applying them to daily database design tasks really isn't all that complicated and it could drastically improve the performance of DBMS.

In this report, I'll introduce the concept of normalization and take brief look at the most common normal forms.

Why to normalize?
While designing a database, the main problem existing in that “raw” database is redundancy. Redundancy is storing the same data item in more one place. A redundancy creates several problems like the following:

1. Extra storage space
2. Entering same data more than once.
3. Deleting data from more than one place.
4. Modifying data in more than one place.
5. Anomalies may occur in the database if insertion, deletion, modification etc are not done properly. It creates inconsistency and unreliability in the database.

To solve these problems, the “raw” database needs to be normalized.

Normalization
Normalization is the process of efficiently organizing data in a database. There are two goals of the normalization process:
• Eliminating redundant data (for example, storing the same data in more than one table)
• Ensuring data dependencies make sense (only storing related data in a table). Both of these are worthy goals as they reduce the amount of space a database consumes and ensure that data is logically stored.
Un-Normalized

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