Foreign keys

Foreign keys are a fundamental concept in databases that help establish relationships between different tables. Think of them as a link or reference: when one table contains a foreign key, it points to the primary key in another table. This linkage ensures that data is consistent and organized. For example, in a database of students and courses, a foreign key in the students' table may reference the course IDs in the courses table. This relationship helps maintain order, ensuring that each student is correctly associated with the courses they are enrolled in.