What is Database Normalization and How Does it Reduce Data Redundancy?

Normalization Explained in Layman's Terms

When dealing with large databases, avoiding data duplication becomes crucial. Normalization is a technique employed to achieve this goal.

Imagine a table listing people and their countries of origin. Instead of storing lengthy country names like "Bosnia & Herzegovina" repeatedly, we use a reference number that points to a country table. This eliminates redundancy, reducing storage space and simplifies future updates if a country undergoes a name change.

Now, let's explore Second Normal Form (2NF). Suppose we have a table tracking people's visited countries. Instead of creating a table with multiple columns for each country visited, we create three tables: one for people, one for countries, and a link table that associates people with visited countries. This design provides flexibility for managing changes and eliminates duplicate rows where possible.

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