What are the three main types of database relationships?

The three main types of database relationships are characterized as one-to-one, one-to-many, and many-to-many.

In a one-to-one relationship, a single record in one table is linked to a single record in another table. This type of relationship is useful when you want to split a table into two for reasons like security or organization without duplicating data.

One-to-many relationships are the most common type found in databases. In this scenario, a single record in one table can be associated with multiple records in another table. For example, a customer can have many orders, but each order can only belong to one customer. This relationship supports hierarchical data organization, where a parent table can have multiple child entries.

Many-to-many relationships occur when multiple records in one table can be associated with multiple records in another table. This is typically implemented using a junction table, which contains foreign keys referencing the primary keys of the two associated tables. For instance, in a student-course relationship, a student can enroll in multiple courses, and each course can have multiple students.

Understanding these three fundamental types of relationships is essential for effective database design as they dictate how data can be structured, accessed, and managed. The other options represent incorrect or less relevant categories that do