Sure! Here is an SEO-friendly HTML answer for the interview question "What is a primary key in a relational database management system (RDBMS)?":

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What is a Primary Key in a Relational Database Management System (RDBMS)?

In a relational database management system (RDBMS), a primary key is a unique identifier for each record in a table. It uniquely identifies each row and ensures that there are no duplicate values in that column. Primary keys play a crucial role in maintaining data integrity and enforcing entity integrity.

Primary keys are used to establish relationships between tables, enforce referential integrity, and provide a quick and efficient way to retrieve data using indexing.

When designing a database, it is essential to carefully choose a primary key that uniquely identifies each record while also being stable and succinct.

Overall, a primary key is a fundamental concept in RDBMS that helps in organizing and accessing data efficiently in a relational database.

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