What is Normalization in Databases?
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Concept
Normalization is the process of organizing data to reduce redundancy and improve data integrity in a relational database.
Key Points
| Normal Form | Rule | Example |
|---|---|---|
| 1NF | Each column holds atomic values | A table where each cell has one value |
| 2NF | 1NF + every non-key depends on the whole key | Split partial dependencies |
| 3NF | 2NF + no transitive dependencies | Move derived fields |
Interview Tips
- Explain trade-offs: joins vs redundancy.
- Use an example schema diagram.
- Mention denormalization in practical systems.
Reference
Source: Database Normalization Explained