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What is a Primary Key in a Database and Why is it Important?

A primary key is a unique identifier for each record in a database table. It ensures that each record can be uniquely identified and helps maintain data integrity by preventing duplicate entries.

Primary keys are important in a database because they serve as a reference point for relationships between different tables. They also help in optimizing query performance by allowing for quicker retrieval of data through indexing.

Overall, the primary key plays a crucial role in ensuring the accuracy, consistency, and efficiency of a database system.

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