Which description matches Delete Cascade?

Which description matches Delete Cascade?

• A. A constraint that deletes child records automatically when a parent is deleted.
• B. A constraint that prevents deleting a parent if children exist.
• C. A constraint that sets child values to NULL on delete.
• D. A constraint that updates foreign keys to default on delete.

Answer: (A)

Delete Cascade means that deleting a row in the parent table automatically removes all related rows in the child table. This behavior is specified by a foreign key constraint with the ON DELETE CASCADE action. It keeps data consistent by preventing orphaned child records, because the delete operation propagates from parent to children. For example, removing a customer would also delete their orders if the orders reference that customer with cascade. This differs from approaches that try to block the delete when children exist, set the child foreign key to NULL, or reset it to a default value.

Delete Cascade means that deleting a row in the parent table automatically removes all related rows in the child table. This behavior is specified by a foreign key constraint with the ON DELETE CASCADE action. It keeps data consistent by preventing orphaned child records, because the delete operation propagates from parent to children. For example, removing a customer would also delete their orders if the orders reference that customer with cascade. This differs from approaches that try to block the delete when children exist, set the child foreign key to NULL, or reset it to a default value.