Description: A recursive relationship in SQL databases refers to a situation where an entity is related to itself. This means that a table can have a relationship with another row in the same table. This type of relationship is common in hierarchical structures, such as in the case of employees reporting to other employees within the same organization. In terms of database design, recursive relationships allow for modeling complex data structures that require a more dynamic and flexible approach. Recursive relationships are implemented using foreign keys that point to the same table, allowing links between records to be established. For example, in an ‘Employees’ table, each employee can have a ‘Manager’ who is also an employee, thus creating a relationship between records in the same table. This type of relationship is fundamental for representing hierarchies, such as family trees, organizational structures, or product categories, where each element can have related sub-elements. Recursive relationships are essential for database normalization, as they help avoid data redundancy and maintain referential integrity.
