MySQL 8.x 中的主要错误?-- 外键

While retrieving foreign keys information from MySQL (for a code generator) I noticed this strange behavior. It looks like a major bug in MySQL 8.x. When I create a foreign key using REFERENCES the engine does not enforce it. For example:

create table p (
  id int primary key not null
) engine=innodb;

create table q (
  pid int references p (id)
) engine=innodb;

insert into q (pid) values (123); -- succeeds (!)

请参阅 DB Fiddle 中的示例.

但是，如果我创建外键键入 FOREIGN KEY (col) REFERENCES table (col) 它可以正常工作:

create table p (
  id int primary key not null
) engine=innodb;

create table r (
  pid int,
  foreign key (pid) references p (id)
) engine=innodb;

insert into r (pid) values (456); -- fails, as expected