Which statement describes Delete Cascade?

Which statement describes Delete Cascade?

• A. Deleting a parent is always blocked if it is referenced by a foreign key.
• B. Deleting a parent sets a default value on all references.
• C. A record can be deleted and all related records with foreign keys are deleted automatically.
• D. Deleting a parent sets all foreign keys to NULL.

Answer: (C)

Delete cascade means that removing a row from a parent table automatically removes all related rows in child tables that reference it. This keeps referential integrity by preventing orphaned records and can simplify cleanup when you want to delete a whole set of related data. For example, with ON DELETE CASCADE on a constraint between departments and employees, deleting a department will also delete all employees in that department. This behavior is different from deletes that are blocked when children exist (restrict), or actions that set the foreign keys to NULL or to a default value (SET NULL, SET DEFAULT). So the essence is that a record can be deleted and all related records with foreign keys are deleted automatically.

Delete cascade means that removing a row from a parent table automatically removes all related rows in child tables that reference it. This keeps referential integrity by preventing orphaned records and can simplify cleanup when you want to delete a whole set of related data. For example, with ON DELETE CASCADE on a constraint between departments and employees, deleting a department will also delete all employees in that department. This behavior is different from deletes that are blocked when children exist (restrict), or actions that set the foreign keys to NULL or to a default value (SET NULL, SET DEFAULT). So the essence is that a record can be deleted and all related records with foreign keys are deleted automatically.