是的。确保您没有孤儿（没有父项的条目），根据用法，如果您定义级联删除，则删除父项时，其所有子项也将被删除。

Yes. Ensures that you don't have an orphan (entry with no parent), and depending on usage, if you define a cascading delete, when a parent is deleted, all its children will also be deleted.

缺点是像任何其他外键一样轻微的性能损失。

Disadvantage would be a slight performance hit just like any other foreign key.