What is the purpose of a junction table in a database?

A junction table serves a crucial function in relational database design, specifically when handling many-to-many relationships between two entities. In a many-to-many relationship, a single record in one table can be associated with multiple records in another table, and vice versa. To effectively manage this complexity, a junction table is created.

The junction table typically contains foreign keys that reference the primary keys of the two tables involved in the relationship. This setup allows each record in the junction table to link a specific entry from one table with a specific entry from the other, thereby creating a bridge between the two tables. For instance, if you have a "Students" table and a "Courses" table, a junction table could link these two, allowing one student to enroll in multiple courses and one course to have multiple students.

While other options present valid aspects of a database, they do not describe the unique role of a junction table. Storing records, addressing security, or adding data fields are functions that can apply to various components of a database but do not specifically capture the linking functionality central to junction tables.