我试图创建过程来删除类别和它们之间的连接，但不幸的是，我不知道如何处理我的关系。

# 1451 - Cannot delete or update a parent row: a foreign key constraint fails (`saver`.`categorytree`, CONSTRAINT `categorytree_ibfk_1` FOREIGN KEY (`parent_id`) REFERENCES `category` (`id`))

以下是我创建的代码：

delete con, cc from categorytree con 
join categorytree ct on con.child_id = ct.child_id
join category cc on con.child_id = cc.id
where con.parent_id = 1

table：

create table category (
id int not null AUTO_INCREMENT,
name varchar (50) not null,
primary key(id) 
);

create table categorytree(
parent_id int not null,
child_id int not null ,
depth int,
FOREIGN KEY (parent_id) references category(id),
FOREIGN KEY (child_id) references category(id)
);

有人能帮忙吗？
编辑： ON DELETE CASCADE 为我做这件事。谢谢。

create table categorytree(
parent_id int not null,
child_id int not null ,
depth int,
FOREIGN KEY (parent_id) references category(id) ON DELETE CASCADE,
FOREIGN KEY (child_id) references category(id) ON DELETE CASCADE
);