Untitled section In a relational database, what is a primary key? * A field used to store binary data A unique identifier for each record in a table A tool for managing database connections A type of data used for complex queries

A primary key is like a VIP badge for records in a relational database. Each primary key must be unique, ensuring that no two rows are identical, which helps maintain order and integrity in the data. Think of it as the secret sauce that makes sure every entry can be identified without any confusion! In real-world applications, primary keys are crucial for efficient data retrieval and relationships between tables. For instance, consider an online bookstore: the primary key could be an ISBN number for books, making it easy to track inventory and manage sales records with precision. It keeps the data organized and accessible!