Normalization and Denormalization in Database

Santosh Beora
2 min readNov 30, 2023

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image credit: AlgoDaily

Introduction:

In the vast world of databases, two principles stand tall, each offering a unique perspective on how to structure data: normalization and denormalization.

In this exploration, we’ll unravel these concepts in plain language, understanding their impact, advantages, disadvantages, and where they find their application.

Normalization: Structuring for Integrity

Definition:
Normalization is akin to organizing a chaotic library. It’s the process of structuring a database to eliminate data redundancy and ensure data integrity.

Objective:
To prevent data anomalies by breaking large tables into smaller, related tables.

Example:
Imagine a table holding both customer information and orders. Normalization divides this table into two: one for customers and another for orders, connected by a shared key like CustomerID.

Advantages:
1. Data Integrity: Minimizes inconsistencies.
2. Flexibility: Allows for easier modification.
3. Optimized Storage: Efficient use of space.

Disadvantages:
1. Increased Joins: Queries may involve more joins, impacting performance.
2. Complexity: Requires a solid understanding of relationships.

Use Cases:
Perfect for transactional systems where data integrity is paramount, such as banking or order processing systems.

Denormalization: Enhancing Query Performance

Definition:
Denormalization is like creating a quick-access version of your library for certain books. It’s the intentional introduction of redundancy to improve query performance.

Objective:
To boost query speed by reducing the need for joins and simplifying data retrieval.

Example:
In a normalized setup, customer and order information might reside in separate tables. Denormalization might duplicate some customer info in the orders table to speed up queries involving both.

Advantages:
1. Query Performance: Accelerates data retrieval.
2. Simplified Queries: Easier to write and comprehend.

Disadvantages:
1. Data Redundancy: Increases the risk of inconsistencies.
2. Update Anomalies: Updates need careful handling to avoid issues.

Use Cases:
Ideal for read-heavy databases or reporting systems where query speed is a top priority.

Conclusion: Striking the Right Balance

The choice between normalization and denormalization is akin to finding the right rhythm in a dance. It depends on the unique requirements of your application. Are you a transactional system, demanding impeccable data integrity? Embrace normalization. Or are you a read-heavy platform, craving speedy queries? Welcome denormalization.

Note

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Santosh Beora

A GCP Data Engineer sharing cutting-edge data insights.For the latest in data engineering! Follow me on LinkedIn : https://www.linkedin.com/in/santosh-beora/