The primary advantage of using a relational database is its ability to structure data in a way that ensures data integrity and facilitates complex queries. By organizing data into tables and defining relationships among them, relational databases allow for easy management, retrieval, and manipulation of large datasets. The use of SQL (Structured Query Language) enables users to perform precise queries and updates while ensuring that data adheres to defined rules. This structured approach aids in minimizing redundancy and helps maintain a coherent dataset over time.